experiments with per (physics education research) chris meyer [email protected]...

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Experiments with PER (Physics Education Research) Chris Meyer [email protected]. ca [email protected] York Mills C. I.

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Experiments with PER(Physics Education Research)

Chris Meyer

[email protected]

[email protected]

York Mills C. I.

Why Change?

• The poor results from my traditional lessons

• Question: What is the most valuable thing kids could be doing when brought together to learn physics?

PER Background

• Physics Education Research has been taking place for 20+ years

• Universities noticed poor results from traditional teaching practices

• Variety of techniques developed (Redish, Teaching Physics with the Physics Suite)

My Situation

• Had experimented with different PER strategies in a piecemeal way

• Needed to adapt university-based materials/designs

• Didn’t know how to pull off a full course

This Presentation

• How I structure the class

• How the activities run

• How I evaluate the students

A Day in the Life

• Homework Comparison (2 min.)

• Opening presentation (10 min.)

• Group Work Activity (60 min.)

• Daily Reading and Note Taking (30 min.)

• Problems (30 min.)

SPH4U: Syllabus Instructor: Mr. Meyer Updated: Feb, 2010 This syllabus contains a list of all classes, topics and homework in the Gr. 12 physics course. You should always take notes from the listed readings. Introduction Topics Homework 1 Course Introduction

How to Be Smart Intro to Group Work

Read course handouts. Actually read the handouts.

2 Taking Notes Measurement

Read pg. 748-9 “Scientific Notation” Worksheet: Numbers and Physics

3 Numbers, Estimations and Fermi Questions Worksheet: Fermi and Numbers

Kinematics 1 Quiz on Introduction Unit

The BIG 5 Equations Intro to Problem Solving

Read pg. 24-7 Problems: pg. 27, #20-21, pg. 37, #9 * Optional - Review: Graphing Kinematics

2 Cooperative Group Problem Solving (CGPS) Problems: pg. 65 #18, 19 a, b

3 CGPS Read pg. 35-8, pg. 65 #21, 26

4 Representations of Motion Read pg. 11-3, 20-4, pg. 14 #15, 16 Worksheet: Converting Graphs of Motion

5 CGPS Problems: pg. 67 #46

6 Kinematics Graphing ILD or Review Problems: pg. 24 #11, pg. 65 #7

7 Test on Kinematics NOTE: 2-D motion, relative motion and projectile motion are not part of this unit.

Opening Presentations

• Present only the essentials for the day’s activity

• Highlight an idea from the previous readings

• Give an alternate view / explanation based on readings or day’s activity

Group Activities

• Group structure based upon U of T Labs and U of Minnesota CGPS

• Guided inquiry activities (Workshop Physics, Physics Sense-Making)

• Physics challenges (CGPS)

• Marked for feedback (assessment)

• Individual quizzes for marks! (evaluation)

Group Structure

• U of T undergrad physics labs is piloting a redesigned course

• CGPS manual

• Our introduction to group work

Guided Inquiry

• Introduction to and focus on concepts• “Open” inquiry lacks direction, students see

different things than we do• Only key calculations• Compare with direct measurements• Based on Workshop Physics (Priscilla Laws,

Dickinson College)• Based on Physics Sense-Making (Elby, U of

Maryland)• Based on Tutorials in Introductory Physics

Workshop Physics

• Major focus is interplay between observations and experiments, and the formalism of definitions and math (the process of science)

• Students need concrete experience with the phenomena

• Focus on smaller quantity of topics to learn thoroughly

SPH4U: Tension and Pulleys

Part A: Tension and Pulleys Suppose you were to hang a mass of 0.5 kg in the various configurations shown below.

1. Predict and measure the tension in the string for configurations A through E.

2. What can you conclude about the force of tension in the string? 3. Configuration F is tricky since the masses are different. Predict how the two scale

readings will compare. See if you can measure this if the system is not moving too fast!

Predicted Measured

FTA = FTA =

FTB = FTB =

FTC = FTC =

FTD = FTD =

FTE = FTE =

m

A

m

B m C

m m D

m m

E

m M

F

M > m

Date: _____________________ Recorder: __________________ Manager: __________________ Skeptic: __________________

Com / Know / Inq / MC: 0 1 2 3 4 5

Physics Sense-Making

• Our preconceptions are based on our life experience

• Not necessarily wrong

• Must learn how to reinterpret them in light of our growing physics understanding

Tutorial 3: Name Section

Counterintuitive ideas: Newton’s third law

The main point of this tutorial is helping you learn more strategies for learning physics concepts that seem to defy common sense.

I. Newton’s third law and common sense According to Newton’s third law, when two objects interact,

The force exerted by object A on object B is equal in strength (but opposite in direction) to the force exerted by object B on object A.

Often, this law makes perfect sense. But in some cases, it seems not to.

Consider a heavy truck ramming into a parked, unoccupied car.

A. (Work together) According to common sense, which force (if either) is larger during the collision: the force exerted by the truck on the car, or the force exerted by the car on the truck? Explain the intuitive reasoning.

B. (Work together) We’ve asked this question of many students, and a typical response goes like this:

I ntuitively, the car reacts more during the collision. (You’d rather be riding in the truck!) So the car f eels the bigger f orce.

Is your group’s explanation in part A similar to or different from this? Explain.

C. (Work together) According to Newton’s third law, which of those forces (if either) is bigger?

D. Experiment. Is this a case where Newton’s third law doesn’t apply? At the front of the room, the TA has set up an experiment that simulates a truck ramming a car. Go do the experiment and record the results here. You can also test whether Newton’s third law holds for other collisions.

2M M

Tutorials in Introductory Physics

• A series of instructional materials using very basic equipment or thought experiments

• Focus on physical concepts and reasoning skills

Physics Challenges

• Context-rich problems• Must make something happen• Reinforces connection between theory

and reality• Making Connections component of the

course• Based on Cooperative Group Problem

Solving (Heller & Heller, U of Minnesota)

Sample Challenges

CGPS: The Scale Challenge!

Do not write on this page! You will need:

One incline, One retort stand, One test-tube clamp, One small object (m < 200 g) Brains

Set up your incline at any angle between 25o and 40o. Your teacher will place a digital balance scale on your incline with your object resting on it. Predict the reading of the scale in grams. Show the results of your calculations before the test! Bonus How would your prediction change if the object and the scale were free to slide down the incline while making the reading?

Sample ChallengesCooperative Group Problem Solving: Washer Drop!

Do not write on this page! Your group will be given a length of string, five washers and some tape. Your challenge is to attach the five washers such that when you release the string and the washers hit the ground, the sound of each hit is evenly spaced. This means a steady clink-clink-clink-clink-clink. Not clink, clink ….. clink, clinkink. Specifications:

There must be a washer at the two ends of the string. You may not change the string’s length.

The bottom washer will be just above the ground when the string is released. Don’t cover the washers with tape otherwise we can’t hear the ‘clink’!

We will test all the strings at the end of class! Bonus We assumed in our calculations that the bottom washer is ‘just’ above the ground. How will the starting height of the lowest washer affect the results of this challenge?

CGPS

Emphasis on:

• Planning a solution

• Abstraction of context-rich situation to physics idealization

• Translation of common speech to physics terminology

• I reinforce this with Fermi questions

Problem: A. Focus the Problem Pictures and Given Information Key Question(s) Key Concepts / Ideas B. Describe the Physics Diagram(s) and Define Quantities

Date: __________________ Recorder: __________________ Manager: __________________ Skeptic: __________________ Com / Know / Inq / MC: 0 1 2 3 4 5

Implementation Challenges

• Some students don’t like group work

• Some students don’t like to do anything

• Some students resist the extra structure for the homework or group work

• Students feel lost without lectures

Evaluation

Knowledge and Understanding

28% Tests

Thinking and Inquiry

14% Group work quizzes

Communication 14% Tests (6%), group work quizzes (6%), note checks

(2 %)

Making Connections

14% Culminating Project (7%) and “Challenges” (7%)

Exam 30%

Success?

• Greater student engagement

• Increased emphasis on writing

• Daily tutoring

• Test results similar to past (but no FCI)

• Personal satisfaction

Resources

• The Physics Suitehttp://www2.physics.umd.edu/~redish/Book/

• Cooperative Group Problem Solvinghttp://groups.physics.umn.edu/physed/Research/CGPS/GreenBook.html

• Workshop Physicshttp://physics.dickinson.edu/~wp_web/wp_homepage.html

• Tutorials in Physics Sense-Makinghttp://www2.physics.umd.edu/~elby/CCLI/index.html

• U of T Undergrad Labshttp://www.upscale.utoronto.ca/Practicals/

• Tutorials in Introductory Physicshttp://www.phys.washington.edu/groups/peg/tut.html