ENERGY PATHWAY

Energy

Energy is transferred when things change or are made to happen but the total amount in the Universe is always the same

Key themes: Energy transfer Energy sources Energy conservation Sustainability and efficiency

ForewordEnergy is considered by some people to be a major exception to the principle that young people should understand ideas before being given labels for them. It is believed that young people benefit from discussing the ideas about energy that they encounter out of school e.g. ‘getting energy from food and fuel’, ‘using energy’, ‘wasting energy’ long before they are able to define energy. Young people should be able to speak with confidence about energy and engage with the is-sues around energy. It is therefore necessary to distinguish the scientific use of energy from the less precise everyday uses. The term ‘energy’ is regularly encountered in everyday life, although it is often difficult to explain clearly what is meant when the term is used. In sci-ence energy is an abstract concept that describes quantitatively a wide variety of phenom-ena. Scientists and engineers use their knowledge of how energy behaves to better under-stand the processes of nature, to create and build new systems and processes, but they still do not fully understand what energy is. Energy is a physics term describing a mathematical principle - something that can not be held or seen. It is not directly sensed, only the processes, events or changes when energy is transferred e.g. when a torch lights up energy is transferred from the battery to the bulb. Without the battery (a chemical store of energy) the torch will not light. It is important that young people can understand and describe how energy behaves (what it does and what it can not do) and the key ideas1 around energy:

1 Teaching about energy – Robin MillarIoP SPT 11-14 materialsInnovations in Practical Work: Energy Storage – Gatsby Science Enhancement Programme

Energy Sources Energy and Heating

Energy Transfer in Systems

Broad overview of the progression in the Energy Pathway

Uses of Energy / Resources and Sustainability

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Energy is something we can not see or touch. Energy is a property of an object and is not actually contained in or stored in ob-

jects. Energy is treated as being able to move or flow from one place to another, with

more or less of it in a particular place. When something happens energy is transferred from one place to another. Places that can transfer energy to somewhere else are called stores of energy (en-

ergy sources). Without a store of energy nothing happens. However, energy does not explain how or why things happen. It is only the ‘potential’ for things to happen.

Energy is conserved - it can not be created or destroyed. The energy transferred from one place (store) always ends up in other places (stores) and at the end there is the same total amount as there was at the beginning.

Energy is dissipated. There is a finite amount of energy in the universe and as en-ergy is transferred it spreads out and becomes less concentrated. Frequently some of the energy is transferred to stores of thermal energy which are dispersed in the environment and are often the final store as it is difficult to transfer this energy to other stores (this energy is frequently referred to as ‘wasted energy’).

Generally people think of energy as a substance, with flow and conservation analogous to that of matter, although not scientifically correct it is considered an acceptable analogy. It is important to avoid talking about ‘energy use’, energy consumption’, ‘using energy’ or ‘consuming energy’ and instead to discuss the consumption or use of energy sources and energy resources2.

As the ASE Scotland publication ‘Science: Interpreting Excellence3’ explains the “exact nature of the word energy is notoriously hard to understand” and “worrying about the precise nature of energy will be a fruitless task.” The aim is for a population who can speak confidently about the behaviour of energy and the key ideas around energy.

StorylineMany processes or events involve changes and require an energy source before they can happen. Energy can be transferred from one place to another in various ways. When energy is transferred frequently some of it ends up in a thermal store of energy that is dispersed in the environment and is often the final store as it is difficult to transfer this energy to other places. Energy cannot be created or destroyed. Some energy sources, such as fossil fuels, are not renewable or renew very slowly and these resources are becoming more difficult to obtain. Different energy sources and ways of transferring energy have different environmental impacts.

Whenever ANY event or change “happens” in the world, some amount of energy is transferred from one “store of energy” to another. Such energy transfers are the key drivers for everything we do or observe. The movement of things can be changed by applying force, e.g. pushing or pulling. Heating can change things, e.g. cooking food, melting solids or turning water to vapour. Electricity can make light bulbs glow. In all these cases, a store of energy is present (e.g. a person pushing/pulling is a store of kinetic energy and a flame is a store of thermal energy), and in the process of change, energy is transferred from one place to another (e.g. from the person to the moving object or from the flame to the food).An object which can transfer energy to something else is called a store of energy. It does not create energy but must obtain it from itself or somewhere else. Objects are stores of energy

2 Robin Millar Teaching about Energy3 Science: Interpreting Excellence. ASE Scotland

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either because of their chemical composition (as in fuels and batteries), their movement, their temperature, their position in a gravitational or other field, or because they are elastic materials that have been compressed or distorted. Energy can be transferred mechanically (e.g. when a moving object collides with a stationary object that starts moving energy is transferred mechanically from the moving object to the stationary object), by heating (e.g. when food is cooked on a barbeque energy is transferred by heating from the flames/hot coals to the food), by radiation (e.g. when have a conversation or surf the internet on your mobile phone energy is transferred by radio waves (a form of radiation) to your phone) and electrically (e.g. when you switch on your computer energy is transferred electrically from the battery/household power supply to the computer). The total amount of energy is always “conserved”: no additional energy is created and none is destroyed. Some is simply transferred from one store to another. There is a fixed amount of energy in the universe and the total amount at all times remains the same. For example, when the Sun heats and lights the Earth, energy is transferred from the Sun by radiation to the Earth and its nuclear store of energy is depleted. Many processes and phenomena, from the production of electricity to the growth of animals and plants, can be explained in terms of the transfer of energy from one place to another. Living things depend on energy transferred from chemical stores of energy in food, which ultimately depends on the process of photosynthesis in plants where energy is transferred from a nuclear store of energy (the Sun) to a chemical store of energy (the plant). Electricity generated from fossil fuels in the first instance transfer energy from chemical stores to thermal stores of energy, these stores are quickly transferred to kinetic stores of energy which produce the electricity that transfers the energy to other stores. Across the world, the demand for energy sources increases as human populations grow and because modern lifestyles depend on them, and the generation of electricity from them. Since some energy sources, such as fossil fuels are non-renewable or renew very slowly, there are concerns about their sustainability and other renewable sources have to be sought, whilst reducing demand by improving the efficiency of the processes in which they are used. There is also the issue of the side effects that human-driven energy transfers can have on the earth’s climate e.g. burning fuels releases carbon dioxide into the atmosphere.The transfer of energy when things happen almost always results in an unwanted thermal store of energy being produced and spread out by conduction or radiation – ‘dissipated’. These thermal stores of energy are sometimes referred to as ‘wasted’ energy because it is difficult to transfer energy from them. Energy is also transferred from systems through friction, often referred to as 'energy loss'. Reducing friction, the dissipation of energy and transfer into unwanted stores improves the efficiency of a system with more energy transferred to the desired stores.Heat is energy that is transferred spontaneously from one body to another as a result of a difference in temperature, and it is associated with the motion of atoms or molecules. Heat moves from an object at a higher temperature to one at a lower temperature until both objects are at the same temperature (described as the two bodies achieving ‘thermal equilibrium’). How quickly this happens depends on the kind of material (conductor or insulator) through which the heat flows. When an object is heated it has a greater thermal store of energy than when it is cold. The greater the thermal store of energy of an object, the faster the atoms and molecules move and vibrate.Most substances can exist as a solid, liquid, or gas depending on temperature. Atoms and molecules are perpetually in motion (a kinetic store of energy). As the temperature of a substance is increased the jostling motions of its molecules in their confined positions become more pronounced, so most substances expand when heated. In solids, the atoms are closely locked together and can only vibrate. At some particular temperature (different

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for different substances) this jostling motion becomes violent enough for molecules to break free from their confined positions. The solid melts to become a liquid. In liquids, the atoms or molecules have a bigger kinetic store of energy, are more loosely connected, and can slide past one another; some molecules may have a large enough kinetic store of energy to escape into a gas. As the temperature is increased, these motions become ever more violent till, at a particular higher temperature (again depending on the substance) molecules break completely free from one another, and the substance ‘boils’ to become a gas. In gases, the atoms or molecules have a greater kinetic store of energy and are free of one another except during occasional collisions. For example the substance ‘water’ exists in the form of a solid (called ‘ice’) at temperatures below 0oC, then as a liquid up to 100oC, then as a gas (called ‘steam’) above that.

[Adapted from Principles and Big Ideas in Science edited by Wynne Harlen]

Different Approaches to Teaching EnergyEnergy is not a tangible substance that can be observed directly, it is a property of an object or system, which can be calculated and given a numerical value. The scientific idea of energy is an abstract, mathematical idea that is hard to define. According to the Nobel Prize winning physicist, Richard Feynman:

“There is a fact, or if you wish a law, governing all natural phenomena that are known to date. There is no exception to this law – it is exact so far as is known. The law is called the conservation of energy. It says that there is a certain quantity, which we call energy, that does not change in the manifold changes which nature undergoes. That is a most abstract idea, because it is a mathematical principle; it says that there is a numerical quantity, which does not change when something happens. It is not a description of a mechanism, or anything concrete; it is just a strange fact that we can calculate some number and when we finish watching nature go through her tricks and calculate the number again, it is the same.”4

It is important to dispel the impression that energy is a real substance. The existing views of energy that young people have should be established and discussed throughout their education.Energy is often introduced by considering different ‘forms’ of energy, for example hot things have ‘heat energy’ and moving things have ‘kinetic energy’. This approach was introduced as an acceptable way of simplifying a difficult idea. There is some criticism of this approach in that it focuses attention on the wrong place - the form of energy, rather than the processes by which energy is transferred - adding little to understanding energy except “verbal ornamentation to descriptions of changes” 5

“Saying that a light bulb ‘transforms electrical energy into light energy’ adds nothing to the simpler (and more scientifically accurate) statement that it ‘emits light when there is an electric current through it.” 4

Instead of thinking about energy as ‘changing/transformed/converted from one form to another’ there is a move towards thinking of it only as energy. Its nature does not change (energy is energy) only its location changes, with more or less of it in a particular place. In the case of a light bulb energy is transferred electrically to the light bulb where it is transferred by light (and heat). Therefore, energy is taught as always staying the same, and instead the focus is on where it is stored and how it moves from one place to another. In this approach the energy sources and stores of energy are identified and transfer is always used to mean from place to place; and not mixed up with being transferred from one form to another. This pathway can be used to teach both approaches.

The key ideas (see foreword) about energy are:

4 Feynman, 1963, p. 4-15 Robin Millar Teaching about Energy

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energy sources and stores of energy how energy is transferred conservation of energy dissipation of energy

AnalogyMoney (a token that represents something) can be a useful analogy when discussing energy. Analogies are not the same as “the real thing” and there is a danger that young people may take them literally6. It is important to discuss the limitations of the analogy – why is energy not like money?

An energy source is necessary for something to happen can be linked to not being able to buy something unless you have money.

People introduced money to make life easier (before money people exchanged different commodities for goods and services) and, similarly, people have invented ways of using energy sources to improve their lives.

When something happens, energy is transferred from one store to another can be related to buying something in a shop, where money (energy) is passed from you (one store) to the shop keeper (another store). If you don’t buy anything (nothing happens) and the money stays in your ‘pocket’ (the energy remains in the store).

Whenever the amount of energy in one store is reduced, the amount in other stores increases by the same amount can be related to the amount of money (energy) you (the original store) and the shop keeper(s) (other store(s)) have before and after an item has been bought. When you buy something you (the original store) have less money (energy) and the shopkeeper(s) (other store(s)) have more.

What can happen is limited by the amount of energy available in the store of energy, which can be related to the amount of money (energy) you (the store) have setting a limit on what can be bought (transferred to other store(s)). The greater amount of money (energy) that you have (a store of energy has), the greater the potential you have to buy things (the store of energy has to make things happen). For example a battery, a small chemical store of energy, can light a torch; while a nuclear power station, a large nuclear store of energy, can provide light and warmth for a number of homes; and the sun, a massive nuclear store of energy, can provide light and warmth for the solar system.

Energy Transfer in Systems: Energy can be transferred:

mechanically (kinetically): by moving objects including sound a mechanical wave propagated by vibrating objects;

by heating: spontaneously from an object at a higher temperature to one at a lower temperature;

by radiation: from a source (e.g. light) through a medium or space by electromagnetic waves (e.g. radio waves and microwaves) that travel and spread out or particles (e.g. nuclear particles, such as neutrons, alpha and beta particles, etc.); and

electrically: by an electric current.

6 Models in STEM document

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Stores of energy:In the early levels the focus is on the energy source - where is the energy transferred from (e.g. batteries, fuels, and people)? Later the stores presented below, selected7 to cover all events that can be described from an energy perspective, can be introduced. For each of these stores, it is possible to calculate and quantify the change in energy as events happen.

chemical: energy stored in reactants (chemicals or combinations of chemicals) that is transferred when they combine or separate;

gravitational potential: the energy that an object possesses because of its position in a gravitational field;

kinetic: the energy an object possesses when it is moving; thermal: the energy of an object that changes when heat is transferred to

it from an object at a higher temperature. It is associated with the motion of atoms or molecules.

elastic potential: the energy an object possesses when it is temporarily stretched or squashed;

vibration: energy stored in mechanical waves and objects (including molecules) vibrating/moving to and fro;

electrical and magnetic field potential: energy stored due to the separation of electrical charges and magnetic poles;

nuclear: energy stored due to the arrangement of nuclear particles in atoms that is transferred when the particles are rearranged through radioactive decay and nuclear reactions.

Forms of energy: kinetic, thermal (heat), light, chemical potential, gravitational potential, elastic potential, electrical, magnetic, nuclear and sound.

At the macroscopic scale energy is associated with multiple phenomena, such as motion, light, sound, magnetic fields, elastic potential, etc. However, at the microscopic scale energy can be modelled as either motions of particles (stores of kinetic, thermal, or vibration energy) or as stored fields, which mediate interactions between particles (stores of chemical, gravitational potential, elastic potential, electrical and magnetic field potential and nuclear)8.

Glossary of terms:Atom – the smallest component of an element (a substance that cannot be separated into a simpler substance) having the chemical properties of the element.Chemical bond – an attraction between atoms that allows the formation of chemical substances containing two or more atoms.Chlorophyll – the green pigment in plants that absorbs sunlight and produces carbohydrates from carbon dioxide and water in a process known as photosynthesis.Conduction – the transfer of stores of thermal energy in a substance from a region at a higher temperature to one at a lower temperature by the interaction of adjacent particles (atoms, molecules, ions, electrons, etc.) in the space between the regions.Convection – the transfer of stores of thermal energy into or out of an object by currents (physical movement) in air or fluid. Convection can arise spontaneously or can be forced by propelling the air/fluid across the object or the object through the air/fluid.Conductors – substances that transfer stores of thermal energy are called conductors and transfer energy at different rates; metals are good conductors, but non-metals and gases are usually poor conductors.

7 IoP SPT 11-14 materials http://www.iop.org/education/teacher/support/spt/page_41531.html 8 A Framework for K-12 Science Education: Practices, Crosscutting Concepts and Core Ideas

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Electromagnetic waves – waves associated with changing electric and magnetic fields resulting from the acceleration of an electric charge. Moving electrons create a magnetic field and when they move back and forth or oscillate their electric and magnetic fields change together forming an electromagnetic wave. Radio waves, microwaves, infrared, visible light, ultraviolet, X-rays and gamma rays are the waves that make up the electromagnetic spectrum. Energy source and Energy Resource – the energy source is the place where the energy is transferred from e.g. batteries and fuels, moving objects (wind and people) and hot objects. Sources of energy that generate electricity are frequently referred to as energy sources (usually renewable) and energy resources (usually non-renewable).Fossil fuel – fuels formed by natural processes from the organic remains of prehistoric animals or plants, such as coal, oil, gas and peat.Friction – a force that resists motion whenever two objects or substances are in contact with each other. On the microscopic scale objects (even ones that look smooth) and substances are rough/have jagged edges and when they slide against each other they drag, creating friction.Heat – Heat is energy that is transferred spontaneously from one body to another as a result of a difference in temperature. It is not a store of energy or the energy contained/stored in a body (see thermal store of energy). Insulators – substances that are poor at transferring thermal stores of energy are called insulators.Molecule – the smallest physical unit of an element (a substance that cannot be separated into a simpler substance consisting of one or more of the same atom) or compound (a substance consisting of two or more different atoms).Non-renewable – energy resources such as coal, oil, natural gas and uranium that either replenish very slowly or not at all, therefore supplies are limited and they will run out at the rate they are being used.Photosynthesis – a chemical process that converts carbon dioxide into sugars, that occurs in plants in the presence of sunlight.Renewable – energy sources from sustainable natural resources such as biomass, geothermal, hydropower, solar, wind, tidal and wave that are replenished and will be available for billions of years (or as long as the sun shines).System – the process/phenomena being studied. Everything outside the system (not part of the process/phenomena being studied) is known as the surrounding environment. The boundary between the system and the surroundings is generally chosen to make the analysis as simple as possible. Only inputs from and outputs to the surroundings are considered when studying the system. Systems can be described as static or sequences of changes over time and through inputs and outputs. An isolated system has no interactions with the sur-roundings.Temperature – Temperature is a measurement of the average kinetic store of energy of the molecules in an object or system. It can be measured quantitatively, e.g. with a thermometer, to calculate the degree of hotness or coldness of a body or environment.Thermal equilibrium – a state in which all parts of a system are at the same temperature

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Early Level Questions: What is necessary for something to happen? Big Idea: An energy source is necessary for something to happen. Energy is not

directly observed or sensed. However, events and processes that are associated with energy can be observed (e.g. light and movement) and sensed (e.g. heat).

Young children cannot understand a complex concept such as energy, but they will have intuitive notions of energy (e.g. it is needed to make things go, run or happen) that should be explored and discussed during the early years. Learning about the concept of energy in the early years can start with the exploration of ‘how things work’ and the energy source. In the early level the focus is on the experience and observation of using toys and devices that require an energy source to make something happen. Investigating living organisms, and simple objects to:

find out what makes them go - people and other living organisms eat food (a fuel) to keep them healthy and active, cars need fuel to move and many toys and devices need to be pushed/pulled/wound up, or supplied with electricity (from batteries or the mains supply),

what happens when they work - they produce sound, light (e.g. torches and devices with display screens), movement (e.g. washing machine and electric fan) or heat (e.g. oven)

and what happens when there is no energy source – they do not work (e.g. wind-up toys without someone to wind it, torches without batteries and electrical devices not plugged in do not work).

The focus at this stage is on where the energy is (the source) in simple systems at the start (i.e. what makes it work), and through observation being able to predict and describe what happens (i.e. where the energy has been transferred to). Objects that produce light, heat and sound can introduce the understanding that things can be observed and measured (e.g. light and dark, hot and cold, quiet and loud). Looking at what happens without the energy source introduces the idea that “an energy source is necessary for something to happen”.

Common Misconceptionsi. In everyday talk energy is associated with activity and keeping things alive, but is often

wrongly considered to be a material substance that is used up. It is seen as being needed, exhibited, possessed, and consumed by living things. Although food and fuels are sources of energy that are consumed, the energy itself is not consumed, but instead it is transferred to another place.

ii. Energy is movement.iii. Energy is the thing that causes events / makes things happen.

Big Ideas & Curriculum for Excellence Experiences & Outcomes I have experienced, used and described a wide range of toys and common appliances. I can say ‘what makes it go’ and say what they do when they work. SCN 0-4aI can collect objects and ask questions to gather information, organising and displaying my findings in different ways. MNU 0-20a

As I listen and take part in conversations and discussions, I discover new words and phrases which I use to help me express my ideas, thoughts and feelings. LIT 0-10aI listen or watch for useful or interesting information and I use this to make choices or learn new things. LIT 0-04a

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Energy Transfer in Systems: MjAn energy source is necessary Mj

for something to happen. MjSCN Mj 0-04a MjMNU Mj 0-20a Mj

LIT 0-10a LIT 0-26a Mj

Curriculum Links, Skills and Interdisciplinary Learning Opportunities Gathering information through observation and exploration Understanding by predicting, describing and sorting based on criteria Communicating and learning through discussion, drawings and simple texts

Discussion of the ways in which living things are ‘energetic’ can be extended to look at non-living things (mechanical and electrical toys) being able to do things. Using the appropriate senses to make purposeful observations about what makes things go and what happens when they work, for example when a wind-up toy is wound up energy is transferred through movement to the spring and stored until

it is transferred back to movement. Activities could include exploring objects and their energy sources, for example a project looking at favourite toys (pupils, parents and grandparents) and sorting them into various categories e.g. what makes them go (movement, electricity, etc.) and what they do (movement, sound, light, etc.), and keeping an energy diary that records the object used, what it does, the source of energy and if it uses electricity. During these activities there are opportunities to start to look at which appliances and toys are electrical, and how to use them safely 9 and wisely (e.g. turning off appliances when they are no longer needed).

Introducing ideas about Science people learn about the world through careful observation and trying things before trying things people sometimes make guesses based on past experiences and

observations one way to describe something is to record what happens it is important to record observations as accurately as possible because it enables

people to compare their findings when people give different descriptions of the same thing, it is a good idea to make

fresh observations and look into the similarities and differences between the descriptions

people seek explanations for why things happen and look for relationships between what is happening and what makes it happen

9 http://www.switchedonkids.org.uk/pt_teachers.html http://www.theiet.org/education/teacherresources/posters/

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First Level Question: What are energy sources?

Big Idea: The sun is a major source of energy supplying the light and heat that are necessary for life. A hot object (such as the sun) can warm a cooler one by contact or at a distance. When warmer things are put with cooler ones, the warmer things get cooler and the cooler things get warmer until they all are the same temperature. Some materials are poor conductors (insulators) and reduce the transfer of energy.Things that give out light often provide warmth at the same time. Living organisms use different energy sources to keep themselves warm. Some source of energy (food) is needed for organisms to stay alive and grow. People have worked out ways of using the energy sources in their environment to stay alive and over the years have invented devices to improve their lives.

The focus at this stage is on identifying energy sources, showing how they are important to survival, essential to everyday life and how they can make our lives more comfortable. A logical place to start is by exploring the sun as a major source of energy, crucial to life on Earth. Linking patterns in nature to the heat and light provided by the sun (e.g. warmer and lighter during the day or in sunny areas and the effect of sun and light on plant growth) can be used to build on the concept that ‘an energy source is necessary for something to happen’ and to introduce the idea that ‘hot objects can warm cooler ones at a distance’. The range of energy sources could be extended by looking at how people used sources of energy in the past (e.g. sun, fuels for fire, windmills, water wheels, steam engines) to meet their needs and by comparing past lives (where sources of energy were used in-situ) with the present day, and our growing dependence on electricity (that can transfer energy from one place to another over a large distance) and devices that rely on an electricity supply.

Common Misconceptionsi. Pupils might have the same views of energy as they do of force – associated with

animate objects and linked to motion.ii. Objects are seen as having energy (and being rechargeable), some as ‘needing’ energy

(and simply expending what they get) and yet others as neutral (and whose activities are somehow ‘normal’ or ‘natural’)10.

iii. Energy resides in objects as an entity.iv. Cold is being transferred and not heat i.e. things get colder instead of their

temperature being raised by a hotter object. v. Some materials are intrinsically warm (blankets) or cold (metals) e.g. a block of ice in a

warm material will melt faster because it is warmed by the material. vi. Some young people think objects that keep things warm are sources of heat and do

not comprehend that they are insulators stopping the heat ‘escaping’.

10 Watts, M - Some alternative views of energy.

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Big Ideas & Curriculum for Excellence Experiences & Outcomes

I am aware of different types of energy around me and can show their importance to everyday life and my survival. SCN 1-04aI can explore examples of food chains and show an appreciation of how animals and plants depend on each other for food. SCN 1-02a Through exploring properties and sources of materials, I can choose appropriate materials to solve practical challenges. SCN 1-15a By exploring the forces exerted by magnets on other magnets and magnetic materials, I can contribute to the design of a game. SCN 1-08a By exploring and using technologies in the wider world, I can consider the ways in which they help. TCH 1-01aI have used a range of ways to collect information and can sort it in a logical, organised and imaginative way using my own and others’ criteria. MNU 1-20b I can compare aspects of people’s daily lives in the past with my own by using historical evidence or the experience of recreating an historical setting. SOC 1-04aI understand that my body needs energy to function and that this comes from the food I eat. I am exploring how physical activity contributes to my health and wellbeing. HWB 1-28aUsing technology and other methods, I can display data simply, clearly and accurately by creating tables, charts and diagrams, using simple labelling and scale. MTH 1-21a

Curriculum Links, Skills and Interdisciplinary Learning Opportunities Gathering information through observation, experimenting, measuring, inquiry and

questioning Applying knowledge from earlier studies and learning from prior/historical events Evaluating by collecting and recording data Understanding by inferring, predicting and explaining Communicating through making and using models, creating texts, discussion and dis-

playing findingsLinking patterns in nature (e.g. establishing that it is warmer and lighter during the day than at night or in sunny areas compared to shady areas, and that puddles dry up and snow melts faster when the sun is shining on them) to the heat and light provided by the sun, can build on the idea that an energy source is necessary for something to happen. Investigations in to the effect of the sun on nature (e.g. plants growing with and without heat and light, cold bloodied animals requiring heat from the sun to regulate their body

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Energy Transfer in Systems: MjWhen something happens Mjenergy is transferred from Mj

one place to another. MjSCN Mj 1-02a MjHWB Mj 1-28a Mj

Energy and Heating: MjA hotter object can Mj

warm a cooler one by Mjcontact or at a distance. Mj

Energy and Heating: MjThings that give out light often Mj

provide warmth at the same time. MjLiving organisms use different Mj

energy sources to keep Mjthemselves warm. Many Mj

mechanical and electrical devices Mjget warmer when they are used. Mj

Energy and Heating: MjWhen warmer things are put with Mj

cooler ones, the warmer things get Mjcooler and the cooler things get Mj

warmer until they all are the same Mjtemperature. Some materials are Mjpoor conductors (insulators) and Mj

reduce the transfer of energy. Mj

SCN Mj 1-15a MjMTH Mj 1-21a Mj

Sources of Energy: MjThe sun is a major source of Mj

energy supplying the light and Mjheat that are necessary for life. Mj

SCN Mj 1-04a Mj

Uses of Energy Sources/ MjResources and Sustainability: MjAn energy source (food a fuel) Mj

is needed for organisms to Mjstay alive and grow. Mj

SCN Mj 1-02a MjHWB Mj 1-28a Mj

Uses of Energy Sources/Resources and MjSustainability: Mj

People have worked out ways of using the Mjenergy sources in their environment to stay Mj

alive and over the years have invented devices Mjto improve their lives. Mj

SCN Mj 1-04a MjTCH Mj 1-01a SOC 1-04a MjMNU Mj 1-20b Mj

temperature and increase their activity) can also introduce the idea that when something happens energy is transferred from one place (the sun) to another (the Earth, plant or animal), and that hot objects can warm colder objects when in contact and at a distance. Investigations into how to keep objects warm and cool11 could begin to explore the transfer of energy from warmer objects to cooler objects, introduce conductors and insulators and provide opportunities to display data in tables, charts and diagrams. Being ‘energetic’ and the transfer of energy from one store to another can be explored further through activities looking at food and health12 and the creation of simple food chains and tracing the transfer of energy through the food chain13 (i.e. from the sun to the plants to the plant eaters (herbivores) to the meat eaters (carnivores) and omnivores (plants and meat) and noting that not all of the original energy from the plant is transferred to the next consumer in the chain, e.g. some of it might be transferred to growth and movement or stored by the consumer). A project into how other civilizations, such as the Scots14, Egyptians and Ro-mans, lived in the ancient world can look at diet, health and how sources of energy in the natural environment were used, e.g. sunlight and fire for heat, light and cooking food, the use of animals, slaves, wind and water to do work e.g. sailing ships, grinding wheat, pumping water from wells, etc., with activities such as building simple sailboats, windmills15 and waterwheels16.

Introducing ideas about Science people learn about the world through careful observation and trying things before trying things people sometimes make guesses based on past experiences and

observations one way to describe something is to record what happens it is important to record observations as accurately as possible because it enables

people to compare their findings oral and written descriptions, graphs, tables, diagrams and models can be used to

represent objects, events and processes in the real world when people give different descriptions of the same thing, it is a good idea to make

fresh observations and look into the similarities and differences between the descriptions

people use techniques, tools and formulas to determine measurements / compare an unknown quantity with a known

people seek explanations for why things happen and look for relationships between what is happening and what makes it happen

11 http://www.powersleuth.org/docs/EHM%20Lesson%201%20FT.pdf http://www.powersleuth.org/docs/EHM%20Lesson%207FT.pdf 12 http://www.bbc.co.uk/schools/scienceclips/teachersresources/ages6_7/tr_health_growth_lp.shtml

13 http://www.mysciencebox.org/foodchain http://www.planetpals.com/foodchain.html http://www.bbc.co.uk/schools/teachers/ks2_lessonplans/science/food_chains.shtml 14 http://www.ltscotland.org.uk/scotlandshistory/index.asp 15 http://library.thinkquest.org/3611/choices/howto.htm http://www.dltk-kids.com/world/japan/morigami-windmill.htm 16 http://www.solarschools.net/resources/pdf/Make%20Your%20Own%20Water%20Wheel.pdf http://howto.wired.com/wiki/Build_a_Plastic_Cup_Waterwheel

12

Second Level Question: Are there differences between energy sources? Big Idea: Energy has a tendency to transfer from where it is ‘more concentrated’ to

where it is ‘less concentrated’. Energy is transferred from one place to another mechanically, electrically, by heating and by radiation (e.g. light and microwaves are forms of radiation that transfer energy). Energy is always conserved. Whenever the amount of energy in one place is reduced, the amount in other places increases by the same amount. Electricity can be generated from a variety of energy sources and is used to transfer energy to other stores.In everyday life fuels (energy resources) are important sources of energy. Fuels are used to bring about a range of processes and events, and are consumed in the process. Burning fuels transfers stores of chemical energy to stores of thermal energy, some stores of thermal energy end up dispersed in the environment and it is difficult to transfer this energy to other stores. Some fuels when burned release carbon dioxide into the atmosphere. A chemical reaction is a series of changes that results in the production of one or more new substances and is always accompanied by the transfer of energy either from or to the new substances. Fossil fuels (coal, oil and gas formed millions of years ago from the remains of dead organisms) are non-renewable energy sources. Only a limited amount of fossil fuels are available and the rate at which they are being used is increasing. Using sources f energy efficiently can prolong the life of some energy resources, reduce pollution and save money.

Investigation into how a range of energy sources (e.g. fuels) are used in everyday life reveals that there are many different energy sources with mul-tiple uses. Further exploration of their uses can lead to the investigation of simple energy transfer processes, e.g. cooking food, turning on lights, generating heat, fo-cusing on key questions such as:

where is the energy stored at the start, where is it transferred to (end up), how is it transferred, and is heat generated in the process?

Examination of the ways in which climate and seasons affect the usage of energy sources can lead to: investigating how different people use energy sources, establishing the impact different lifestyles can have on energy sources, monitoring the consumption of fuels and discovering how energy sources can be used wisely.Building on the idea that energy sources are essential to everyday life, the importance of fuels can be introduced by exploring: society’s growing dependence on energy sources since the industrial revolution; its present reliance on electricity and fossil fuels; the increasing rate at which fossil fuels are being used and starting to consider the hunt for alternative en-ergy sources.

Common Misconceptionsi. The terms ‘energy use’ and ‘energy consumption’ should be avoided as they can cause

problems later on when energy conservation is introduced. Alternatives include ‘fuel use’, ‘fuel consumption’ and ‘energy resources’.

ii. ‘Energy conservation’ has a new specialised meaning concerned with technologies for economic use of fuel resources. The use of the term ‘energy’ in this context of saving fuel resources often slides between two contradictory meanings – as something which

13

is used up (reinforcing the everyday meaning) and as something that is conserved (which pupils find difficult to reconcile with their own understanding of energy).17

iii. Energy is a fuel or something that is stored, ready to use and gets used up.iv. Energy is a by product of the situation, similar to a waste product.v. Energy is a dormant ingredient that needs some ‘trigger’ to release it, for example

food is not seen as a source of energy but as something that triggers the production of energy in the body.

Big Ideas & Curriculum for Excellence Experiences & Outcomes

By considering examples where energy is conserved, I can identify the energy source, how it is transferred and ways of reducing wasted energy. SCN 2-04a I can use my knowledge of the interactions and energy flow between plants and animals in ecosystems, food chains and webs. I have contributed to the design or conservation of a wildlife area. SCN 2-02aThrough exploring non-renewable energy sources, I can describe how they are used in Scotland today and express an informed view on the implications for their future use. SCN 2-04b

17 STTIS Teaching about energy

14

Energy Transfer in Systems: MjEnergy is transferred from one place to Mj

another mechanically (by moving objects), Mjelectrically (by an electric current), by heating Mj

(spontaneously from an object at a higher Mjtemperature) and by radiation (e.g. travelling Mj

electromagnetic waves such as light). Mj Mj

SCN Mj 2-04a Mj

Energy Transfer in Systems: MjEnergy is always conserved. Whenever the Mjamount of energy in one place is reduced, Mjthe amount of energy in the place(s) it is Mj

transferred to increases by the same amount. MjAs energy is transferred it becomes more Mj

spread out (dissipated) and there are fewer Mj'concentrated' stores available. Mj

SCN Mj 2-04a MjSCN Mj 2-02a MjEnergy Transfer in Systems: Mj

Energy has a tendency to transfer Mjfrom where it is 'more concentrated' Mj

to where it is 'less concentrated'. MjSCN Mj 2-04a Mj

Energy Transfer in Systems: MjA chemical reaction is a series of changes Mj

that results in the production of one or Mjmore new substances and is always Mj

accompanied by the transfer of energy Mjeither from or to the new substances. Mj

SCN Mj 2-19a MjSources of Energy: MjLight (a form of radiation) transfers Mjenergy from the sun, with a fraction Mjof that energy transferred to Earth. Mj

SCN Mj 2-11b Mj

Sources of Energy: MjIn everyday life fuels (energy Mj

resources) are important Mjenergy sources. Mj

SCN Mj 2-04b MjHWB Mj 2-28a Mj

Uses of Energy Sources/ MjResources and Sustainability: Mj

Fuels are used to transfer Mjenergy, to bring about a range Mjof processes and events, and Mjare consumed in the process. Mj

SCN 2-04b HWB 2-28a Mj

Sources of Energy: MjFossil fuels (coal, oil and gas formed Mj

millions of years ago from the Mjremains of dead organisms) are Mjnon-renewable energy sources. Mj

Only a limited amount of fossil fuels Mjare available and the rate at which Mjthey are being used is increasing. Mj

SCN 2-04a SCN 2-04b MjSOC 2-09a TCH 2-02a Mj

Uses of Energy Sources/Resources and MjSustainability: Mj

Electricity can be generated from a variety of Mjenergy sources and is used to transfer Mj

energy to other stores. Electrical circuits Mjprovide a means of transferring energy and Mj

in the process can bring about chemical Mjchanges, and produce heat, light and sound. Mj

SCN 2-09a SCN 2-10a Mj

Uses of Energy Sources/Resources and MjSustainability: Mj

Using energy sources efficiently can Mjprolong the life of some energy resources, Mj

reduce pollution and save money. MjSCN 2-04b TCH 2-02a Mj

SCN 2-20a SOC 2-08a SOC 2-09a MjLIT 2-18a MTH 2-21a Mj

Uses of Energy Sources/Resources and MjSustainability: Mj

Burning fuels transfers large amounts of energy Mj(stores of chemical energy are transferred to Mj

stores of thermal energy) emitting heat and light Mjin the process, and some fuels release carbon Mjdioxide into the atmosphere; some of the store Mj

of thermal energy ends up dispersed in the Mjenvironment which is often the final store as it is Mj

difficult to transfer this energy to other stores. Mj MjSCN Mj 2-04b MjSCN Mj 2-19a Mj

I have used a range of electrical components to help to make a variety of circuits for differing purposes. I can represent my circuit using symbols and describe the transfer of energy around the circuit. SCN 2-09aTo begin to understand how batteries work, I can help to build simple chemical cells using readily-available materials which can be used to make an appliance work. SCN 2-10aI have collaborated in activities which safely demonstrate simple chemical reactions using everyday chemicals. I can show an appreciation of a chemical reaction as being a change in which different materials are made.SCN 2-19aThroughout all my learning, I take appropriate action to ensure conservation of materials and resources, considering the impact of my actions on the environment. TCH 1-02aHaving analysed how lifestyle can impact on the environment and Earth’s resources, I can make suggestions about how to live in a more sustainable way. TCH 2-02aI can explain the links between the energy I use while being physically active, the food I eat, and my health and wellbeing. HWB 2-28aBy exploring reflections, the formation of shadows and the mixing of coloured lights, I can use my knowledge of the properties of light to show how it can be used in a creative way. SCN 2-11b Through research and discussion I have an appreciation of the contribution that individuals are making to scientific discovery and invention and the impact this has made on society. SCN 2-20a I can discuss why people and events from a particular time in the past were important, placing them within a historical sequence. SOC 2-06aI can discuss the environmental impact of human activity and suggest ways in which we can live in a more environmentally-responsible way. SOC 2-08aHaving explored the ways journeys can be made, I can consider the advantages and disadvantages of different forms of transport, discussing their impact on the environment. SOC 2-09aI can display data in a clear way using a suitable scale, by choosing appropriately from an extended range of tables, charts, diagrams and graphs, making effective use of technology. MTH 2-21a To help me develop an informed view, I can identify and explain the difference between fact and opinion, recognise when I am being influenced, and have assessed how useful and believable my sources are. LIT 2-18a

Curriculum Links, Skills and Interdisciplinary Learning OpportunitiesA useful introductory activity to fuels18 is to divide a given list into ‘things that need fuel’ and ‘things that do not need fuel’. This can lead to activities and discussions about: the range of fuels used in everyday life, the amounts used in different areas of life (home, school, transport, work places, etc.), how the total amounts have changed over time,19 and the differences in amount (and type) of fuel20 used in different regions of the world and the consequences of this.Exploring food as a source of energy can introduce the idea that amounts of energy can be measured (preferably using the energy information based on kilojoules) through health and physical activities looking at daily energy requirements and the relationship between food as a fuel, which the body converts through chemical changes into other substances and movement21, and during these processes energy is transferred from the food to other places. The transfer of energy and concept of energy conservation can be explored by tracing the ‘flow’ of energy through balanced and unbalanced food chains and webs22 (tokens can be used to represent the amount of energy in the different stores). Research into the Scottish engineer James Watt’s invention of the Boulton and Watt steam engine credited with starting the industrial revolution in the 18 th century, 18 Robin Millar Teaching about Energy19 http://www.scotland.gov.uk/Publications/2009/10/16124856/3 20 Electricity generation by fuel used http://www.statistics.gov.uk/STATBASE/ssdataset.asp?vlnk=7286 21 http://www.abc.net.au/science/surfingscientist/pdf/lesson_plan13.pdf http://www.bioedonline.org/resources/files/TG_food.pdf22 http://mypages.iit.edu/~smart/hearlyv/lesson1.htm

15

could examine how this advance in technology led to society’s growing dependence on the consumption of fossil fuels23 and the reliance today on fuels to generate electricity. The in-formation gathered could be used in a fuel history timeline (e.g. using drawings and/or video 24) tracking the main types of fuels over the ages, from early man through the agricultural re-volution and industrial revolution, and moving forward to globalisation and the future. Investigations into circuits and batteries could be a starting point for looking at where the electricity in homes, schools, etc., comes from. Possible activities include learning about the different sources of energy used to generate electricity25 and piecing together the electric journey26 from these sources to the end user. Exploration of how sources of energy (e.g. electricity and fuels) are used in homes and schools can look at monitoring their consump-tion (energy audits) and ways of reducing waste (conserving energy)27. The impact of lifestyle choices can be investigated by comparing power bills from different households, the Walk a Mile in My Shoes - Carbon Critters28 activity, online tools to calculate ecological footprints29, etc. The use of energy sources can vary depending on the climate, time of day and season.

Further activities could involve comparing the use of energy sources during different seasons, how they are used by other cultures in different climates (e.g. exploring location, the sources that are obtainable and the use of ‘free’ energy sources in developing countries e.g. solar fridges30 and cookers31 (a summer activity) and PlayPumps32) and the impact of the way different cul-

tures live. Investigating the use of solar energy (e.g. cookers and fridges) could encompass looking at the properties of light and the conditions that affect light transferring energy e.g. materials that reflect or absorb light.The data collected in activities such as monitoring fuel consumption, comparing bills, calcu-lating ecological footprints could be displayed using tables, charts, diagrams and graphs.During activities and discussions there will be opportunities to look at how energy is trans-ferred in simple systems (e.g. in the PlayPump the energy stored in food is transferred mech-anically to the water stored above ground) using explanations such as, the energy is:

transferred from X to Y, going from here to here (e.g. from the battery to the bulb) energy flows from the hotter object to the colder object, ‘more concentrated’ here at the start but some of it is transferred here (e.g. concen-

trated in the sun but some of it is transferred to the plants that has been warmed by the sun).

23 http://www.nationalgrideducation.com/primary/pupils/interactives/drop_of_oil/fullscreen.php24 http://www.milkandcookies.com/link/229565/detail/ - WARNING: this video contains the phrase ‘all hell breaks loose’25 http://www.eia.gov/kids/energy.cfm?page=2 26 http://www.powersleuth.org/teacher/energy-lights/lesson6-overview http://powerup.ukpowernetworks.co.uk/under-11/electric-journey.aspx 27 SSERC SSA Tasks – Saving Energy (Electricity for enterprise - Lesson 11) http://www.energyhog.org/adult/pdf/vampire_hunt.pdf vampire_hunt.pdf (application/pdf Object) 28 http://www.greenlearning.ca/eneraction/teacher-materials29http://scotland.wwf.org.uk/what_we_do/working_with_schools/education_resources/ and http://carboncalculator.direct.gov.uk/index.html and http://www.planet-positive.org/how_2_calculator.php 30 http://home.howstuffworks.com/solar-powered-refrigerator2.htm http://www.solarpowerwindenergy.org/2009/02/04/student-invents-solar-powered-fridge-for-developing-countries/ 31 http://solarcooking.wikia.com/wiki/Category:Solar_cooker_plans http://www.re-energy.ca/solar-oven 32 http://www.waterforpeople.org/extras/playpumps/how-playpumps-works.html

16

Storyline - Third Level Question: How is energy transferred in systems? Big Idea: The total energy within a defined system changes only by the transfer of

energy in to or out of the system and usually results in some energy being trans-ferred ('escaping') into its surrounding environment (e.g. the transfer of energy from a system through friction). Some systems are more efficient at transferring energy than others (e.g. reducing friction improves efficiency). Sometimes when energy ap-pears to be lost it has been transferred to a system that is so large the effect of the transferred energy is imperceptible. Energy is transferred from the sun by radiation (electromagnetic waves - radio waves, microwaves, infrared radiation, visible light, ultraviolet radiation, x-rays, and gamma rays) to plants that contain chlorophyll and they produce sugars from carbon dioxide and water through a process called photosynthesis. The chemical bonds of food molecules are a chemical store of energy and energy is transferred when the bonds are broken and new compounds with lower energy bonds are formed. Chem-ical stores of energy are associated with the configuration of the atoms and mo-lecules that make up a substance. During chemical reactions energy is transferred when atoms and molecules are separated or combined. Most substances can exist as a solid, liquid, or gas depending on temperature. In solids, the atoms are closely locked together and can only vibrate. In liquids, the atoms or molecules have higher energy, are more loosely connected, and can slide past one another; some molecules may get enough energy to escape into a gas. In gases, the atoms or molecules have still more energy and are free of one another ex-cept during occasional collisions. Temperature is a measure of the average energy associated with the disordered microscopic motion of individual atoms and mo-lecules (kinetic stores) in a substance. It does not depend on the number of particles. Thermal stores of energy are associated with the disordered motions of atoms or molecules. Over time a store of thermal energy tends to spread out through a sub-stance and from one substance to another if they are in contact, flowing from high temperature regions toward lower temperature regions. They can be transferred through a medium (conduction), by currents in air or fluids (convection), or by elec-tromagnetic waves (radiation). When the transfer of energy to the substance is stopped the substance tends to cool down, transferring its store of thermal energy until it reaches the temperature of the surroundings.Sustainable natural energy sources, such as the sun, wind, water, geothermal and the ocean, will be available for billions of years. Energy sources have costs, benefits, ethical and other implications to society. There are different societal benefits, ad-vantages and disadvantages, and challenges in harnessing renewable and non-re-newable energy sources.

Learners start to explore the transfer of energy within systems, and between the system and its surroundings and to represent the transfer of energy in the system diagrammatically33. The concept of energy transfer is used to track changes in systems by examining simple pro-cesses/events where the initial and final energy store(s) are well defined, and the start and end of the process/event clearly identified.

Developing the conceptual story of energy through energy transfer by heat-ing is perceived to be more intuitive for learners to grasp and thermal stores of energy are often introduced before other stores. Examining thermal

33 http://www.sep.org.uk/energynow.asp

17

stores of energy and their transfer by conduction, convection and radiation links to the big idea that ‘all material in the world is made of very small particles’. Further connections asso-ciating energy with the internal motions and forces affecting the constituent particles that matter is made up of include the structure of solids, liquids and gases and temperature (a measure of the average kinetic store of energy of the particles and molecules within a ma-terial/substance). Key concepts behind the transfer of thermal stores of energy and changes of state lay the conceptual groundwork for understanding climate and atmospheric pro-cesses, such as cloud formation, ocean currents and atmospheric circulation.The progression from non-renewable energy sources leads to the investigation of renewable energy sources, the comparison of the advantages and disadvantages of different energy sources and the challenges harnessing them.

Common Misconceptionsi. Energy said to be ‘lost’ when it is no longer useful energy (e.g. dissipated energy and

energy transferred by friction) can cause confusion with the concept that energy is always conserved.

ii. When considering energy conservation some young people believe energy is ‘produced’.

iii. Confusion with the conservation of energy being related to conserving energy resources that are used up.

iv. Energy efficiency is misunderstood as meaning quick and convenient.v. The principle of the conservation of energy is easy to misunderstand as implying

storage of energy within the system. Teaching about dissipation and degradation of energy before conservation can eliminate much of this misunderstanding. If reworded to give a positive indication of its role as an accounting sheet for energy, the principle becomes easier to use in simple school problems.

vi. Young people find it difficult to distinguish between heat and temperature. vii. In everyday language heat is something a hot object possesses and differs from its

scientific meaning – if heat is added its temperature rises and if it loses heat its temperature falls. Instead of talking about heat the idea that energy is being transferred due to a temperature difference can be introduced – ‘energy is transferred from the hot object to the cold one; this process is called heating’. However, it is difficult to avoid the word heat and one way round this is to use the term ‘thermal store of energy’ which most pupils will probably consider to be a synonym for heat. 34

viii. Young people think of temperature as a ‘property’ of the material – a mixture of hot and cold inside an object, with some materials/substances naturally warmer or colder.

ix. The idea that temperature is a means of measuring heat.x. The idea that a thermal store of energy or heat always rises can develop from

confusion with the fact that hot air rises.xi. Heat is a substance like air which can flow in and out of objects.

xii. Cold is an entity like heat and is the property of a material/substance; cold is the opposite of heat

xiii. Cold is transferred to hotter objects instead of heat being transferred to colder objects.

34 Teaching about Energy Robin Millar

18

xiv. Young people think that materials are either conductors or insulators and do not recognise that the ability of materials to conduct or insulate is on a ‘sliding scale’ e.g. metals are better conductors than glass.

Big Ideas & Curriculum for Excellence Experiences & Outcomes

19

Energy Transfer in Systems: MjThe total energy within a defined system changes only Mjby the transfer of energy in to or out of the system and Mjusually results in some energy transferred ('escaping') Mjinto its surrounding environment. Some systems are Mj

more efficient at transferring energy than others. MjSometimes when energy appears to be lost it has Mj

been transferred to a system that is so large the effect Mjof the transferred energy is imperceptible. Mj

SCN Mj 3-07a MjTCH Mj 3-12a Mj

Energy Transfer in Systems: MjFriction - a force resisting movement when two Mj

objects or substances are in contact - can transfer Mjenergy mechanically and by heating to stores of Mj

vibration energy and thermal energy. The transfer of Mjenergy from a system through friction is often referred Mj

to as 'energy loss'. Reducing friction improves the Mjefficiency of the system with more energy transferred Mj

from or retained in the desired stores. Mj

SCN Mj 3-07a MjTCH Mj 3-12a Mj

Energy and Heating: MjMost substances can exist as a solid, liquid, or gas Mjdepending on temperature. Atoms and molecules Mjare perpetually in motion. Increased temperature Mj

means greater motion, so most substances expand Mjwhen heated. In solids, the atoms are closely Mj

locked together and can only vibrate. In liquids, the Mjatoms or molecules have higher energy, are more Mjloosely connected, and can slide past one another; Mjsome molecules may get enough energy to escape Mjinto a gas. In gases, the atoms or molecules have Mj

still more energy and are free of one another Mjexcept during occasional collisions. Mj

SCN Mj 3-05a Mj

Energy and Heating: MjThermal stores of energy are associated with the Mj

disordered motions of atoms or molecules. Over time Mja store of thermal energy tends to spread out through Mj

a substance and from one substance to another if Mjthey are in contact. Thermal stores of energy flow Mj

from high temperature regions toward lower Mjtemperature regions. They can be transferred Mj

through a medium (conduction), by currents in air or Mjfluids (convection), or by electromagnetic waves Mj

(radiation). When the transfer of energy to the Mjsubstance is stopped the substance tends to cool Mj

down, transferring its store of thermal energy until it Mjreaches the temperature of the surroundings. Mj

SCN Mj 3-04a Mj

Energy and Heating: MjThermal stores of energy can be Mj

transferred by convection in a fluid or gas. MjRegions that have different temperatures Mjhave different densities and under gravity Mj

rise or fall, creating currents that Mjcontribute to the transfer of energy. Mj

SCN Mj 3-04a Mj

Energy and Heating: MjTemperature is a measure of the average Mj

energy associated with the disordered Mjmicroscopic motion of individual atoms and Mjmolecules (kinetic stores) in a substance. It Mj

does not depend on the number of particles. A Mjhigher concentration of energy will lead to a Mj

higher temperature, and a lower concentration Mjof energy to a lower temperature. Mj

SCN Mj 3-04a Mj

Energy and Heating: MjThermal stores of energy transferred by Mj

radiation do not require a medium to Mjpropagate and can travel through air, solid Mjmaterials, and the vacuum of space. The Mjphysical properties of an object determine Mjthe ability of the object to absorb or reflect Mjradiation. Dull, rough surfaces are better Mjabsorbers and emitters of radiation and Mj

smooth polished surfaces are usually good Mjat reflecting radiation and poor emitters. Mj

SCN Mj 3-04a Mj

Sources of Energy: MjEnergy is transferred by radiation from the sun Mj

to plants that contain chlorophyll and they Mjproduce sugars from carbon dioxide and water Mj

through a process called photosynthesis. MjSugars produced by plants are an energy Mj

source which they can use immediately, store Mjfor later use or other organisms can use. Mj

SCN Mj 3-02a Mj

Sources of Energy: MjEnergy is transferred from the sun in Mj

electromagnetic waves and the human Mjeye can detect only a small portion of Mj

this broad spectrum called visible light. MjElectromagnetic waves (radio waves, Mjmicrowaves, infrared radiation, visible Mjlight, ultraviolet radiation, x-rays, and Mjgamma rays) are a form of radiation. Mj

SCN Mj 3-11b Mj

Sources of Energy: MjThe chemical bonds of food Mj

molecules are a chemical store Mjof energy. Energy is Mj

transferred when the bonds of Mjfood molecules are broken and Mj

new compounds with lower Mjenergy bonds are formed. Mj

HWB Mj 3-31a Mj

Energy and Heating: MjThermal stores of energy transferred by Mj

conduction require a medium to propagate. MjStores of thermal energy are conducted from Mjthe hot end of an object/substance to the cold Mj

end. The way the particles are organised in Mjsolids make them better conductors than Mj

liquids. Metals are good conductors, but non- Mjmetals and gases are usually poor Mj

conductors and are called insulators. MjSCN Mj 3-04a Mj

Energy Transfer in Systems: MjChemical stores of energy are Mj

associated with the configuration of the Mjatoms and molecules that make up a Mjsubstance. During chemical reactions Mjenergy is transferred when atoms and Mjmolecules are separated or combined. Mj

SCN Mj 3-19a Mj

I

have collaborated on investigations into the process of photosynthesis and I can demonstrate my understanding of why plants are vital to sustaining life on Earth. SCN 3-02aI can use my knowledge of the different ways in which heat is transferred between hot and cold objects and the thermal conductivity of materials to improve energy efficiency in buildings or other systems. SCN 3-04aBy investigating renewable energy sources and taking part in practical activities to harness them, I can discuss their benefits and potential problems. SCN 3-04bBy contributing to experiments and investigations, I can develop my understanding of models of matter and can apply this to changes of state and the energy involved as they occur in nature. SCN 3-05aBy contributing to investigations of energy loss due to friction, I can suggest ways of improving the efficiency of moving systems. SCN 3-07aBy exploring radiations beyond the visible, I can describe a selected application, discussing the advantages and limitations. SCN 3-11bThrough experimentation, I can identify indicators of chemical reactions having occurred. I can describe ways of controlling the rate of reactions and can relate my findings to the world around me. SCN 3-19aI can explain some of the processes which contribute to climate change and discuss the possible impact of atmospheric change on the survival of living things. SCN 3-05b Through research and discussion, I have contributed to evaluations of media items with regard to scientific content and ethical implications. SCN 3-20b I can investigate the use and development of renewable and sustainable energy to gain an awareness of their growing importance in Scotland or beyond. TCH 2-02b From my studies of sustainable development, I can reflect on the implications and ethical issues arising from technological developments for individuals and societies. TCH 3-02a By applying my knowledge and skills of science and mathematics, I can engineer 3D objects which demonstrate strengthening, energy transfer and movement. TCH 3-12aI can identify the possible consequences of an environmental issue and make informed suggestions about ways to manage the impact. SOC 3-08aBy comparing settlement and economic activity in two contrasting landscapes, I can reach conclusions about how landscapes influence human activity. I can explain my findings clearly to others. SOC 3-13a Through practical activities using different foods and drinks, I can identify key nutrients, their sources and functions, and demonstrate the links between energy, nutrients and health. HWB 3-31a

Curriculum Links, Skills and Interdisciplinary Learning OpportunitiesInvestigating thermal stores of energy and their transfer could involve designing and building energy efficient homes35.

Renewable energy sources could be introduced by looking at Scotland’s natural resources (e.g. North Sea oil, a rainy climate, etc.), its current use of energy sources36 and the move towards a more sustainable future reliant on renewable sources of energy such as wind, wave and tidal. Recent media

items (e.g. oil spills, nuclear disasters and opposition to wind farms) could act as a starting point to discussions on the advantages and disadvantages of different energy sources and the challenges of harnessing different energy sources. Cross curricular activities with social

35 http://www.ltscotland.org.uk/stemcentral/contexts/energysavinghouse/about/index.asp 36 http://www.scotland.gov.uk/Topics/Business-Industry/Energy/Energy-sources and http://www.scotland.gov.uk/Topics/Business-Industry/Energy/Facts/

20

Sources of Energy: MjSustainable natural energy sources, such Mj

as the sun, wind, water, geothermal and the Mjocean, will be available for billions of years. MjThese energy sources - called renewable - Mj

are not consumed in the process or Mjreplenished. Mj

SCN Mj 3-04b MjTCH Mj 2-02b Mj

Uses of Energy Sources/Resources and MjSustainability: Mj

Energy sources have costs, benefits, ethical Mjand other implications to society. There are Mjdifferent societal benefits, advantages and Mj

disadvantages, and challenges in harnessing Mjrenewable and non-renewable energy sources. Mj

SCN Mj 3-04b MjTCH Mj 3-02a MjSCN Mj 3-05b Mj MjSOC 3-08a SOC 3-13a Mj

studies exploring the energy sources available in different localities37 and the impact on the environment. Comparison of renewable and non-renewable energy sources also provides opportunities to consider energy sources in relation to climate change and the greenhouse effect. The process of photosynthesis could be used to link energy transfer by radiation, the electromagnetic spectrum, chemical stores of energy and the transfer of energy when chemical bonds are broken or formed. Practical investigations could look at the effect of heating and light on the rate of reaction, for example monitoring oxygen production in Elodea plants under different conditions38.

37 http://www.ltscotland.org.uk/stemcentral/contexts/renewables/index.asp 38 http://www.practicalbiology.org/areas/intermediate/energy/photosynthesis/investigating-factors-affecting-the-rate-of-photosynthesis,45,EXP.html

21

STEM-ED Scotland is hosted by the University of Glasgow

The research team gratefully acknowledges the support of the colleagues, individuals, groups and organisations that have contributed to the development of this work.The research team acknowledges the financial support from the Scottish Government. They would also like to express gratitude for the financial support and encouragement from the Esmée Fairbairn Foundation that enabled them to begin working on learning progressions in STEM.

List of sources consulted

A Learning Progression for Deepening Students’ Understandings of Modern Genetics Across the 5th–10th Grades. Journal of Research in Science Teaching (2009) Ravit Golan Duncan, Aaron D. Rogat, Anat Yarden.

Another go at energy. Gary Williams and Tony Reeves (2003) Physics Education.

Atlas of Science Literacy. AAAS (2001) Washington, DC: AAAS and NSTA.

Benchmarks for Science Literacy. AAAS (American Association for the Advancement of Science (1993). Project 2016. Oxford University Press.

Curriculum Focal points for Prekindergarten through Grade 8 Mathematics: A Quest for Coherence. (2006) National Council of Teachers of Mathematics.

Curriculum coherence: an examination of US mathematics and science content standards from an international perspective. William H. Schmidt; Hsing Chi Wang; Curtis C. McKnight. (2010) Journal of Curriculum Studies.

Developmental Growth in Students’ Concept of Energy: Analysis of Selected Items from the TIMSS Database. Xiufeng Liu and Anne McKeough. (2005) Journal of Research in Science Teaching.

Differences, energy and change: a simple approach through pictures. Boohan, R. and Ogborn, J. (1996). School Science Review.

How children learn about energy, or Does the first law come first? Solomon, J. (1982). School Science Review.

Learning Progressions in Science. Prepared by Tom Corcoran, Frederic A. Mosher, Aaron Rogat. (2009) Consortium for Policy Research in Education, An Evidence-based Approach to Reform, Center on Continuous Instructional Improvement Teachers College–Columbia University.

Making Sense of Secondary Science. Driver, R., Squires, A., Rushworth, P., and Wood-Robinson, V. (1994). Routledge Publishers, London.

Mathematical Misconceptions. Anne D. Cockburn and Graham Littler. (2008) Sage Publications Ltd, London, UK.

Mathematics in Nursery Education. Ann Montague-Smith. (2002) David Fulton Publishers Ltd, London, UK.

Misconceptions in Primary Science. Michael Allen. (2010) Open University Press.

National Science Education Standards (1996) Center for Science, Mathematics, and Engineering Education (CSMEE)

Principles and big ideas of science education, edited by Wynne Harlen (2010).

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Strand Maps of the 2001/2006 MA Science and Technology/Engineering Standards. Office for Mathematics, Science, and Technology Engineering (OMSTE). www.doe.mass.edu/omste/maps/default.html

Some alternative views of energy. D Michael Watts. (1983) Physics Education.

Support Physics Teaching: 11-14. Institute of Physics. www.talkphysics.org

Sustainable Energy — without the hot air. David JC MacKay. (2009) UIT Cambridge Ltd, England, UK. www.withouthotair.com

Taking science to school: learning and teaching science in grades K-8, by Richard Alan Duschl, Heidi A. Schweingruber, Andrew W. Shouse; (2007) National Research Council (U.S.)

The teaching of Science in Primary Schools. Wynne Harlen (2000). David Fulton Publishers Ltd, London, UK.

Teaching about energy. Robin Millar (2005) The University of York.

Teaching about energy and energy transfer. Mike Evans and Linda Ellis (2001). www.scienceonline.co.uk

Teaching and learning about energy in New Zealand secondary school junior science classrooms. Malcolm Carr and Valda Kirkwood (1988) Physics Education.

Teaching energy: thoughts from the SPT11–14 project. Ian Lawrence. (2007) Physics Education.

Teaching the conservation of energy. Joan Solomon (1985) Physics Education.

Websites

Curriculum for Excellence. Learning Teaching Scotland www.ltscotland.org.uk

Gatsby Science Enhancement Programme www.sep.org.uk

Scottish Qualifications Arrangements Documents. SQA www.sqa.org.uk

STEM-ED Scotland, University of Glasgow, 12A The Square, GLASGOW, G12 8QQ

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