EXPERIMENTAL DESIGN

Testable Question

After and observation a question is generated.

A good question is specific and uses what and how.

Leads readers into the experiment

Example: How high would a rose plant grow if the amount of water varied?

Hypothesis

If….then… NOT just an “educated guess”. Very specific regarding details (amounts,

units, time, number of trails…) Eg) If 10mL of water is added to rose

plant A and 20mL of water is added to rose plant B, then rose plant A will grow taller than rose plant B.

Can you identify the variables (IDV,DV)?

Variables Independent Variable (IDV): the variable that

is changed/manipulated by the experimenter. Dependent Variable (DV): the variable that

changes as a result of what the experimenter changes (the variable that is measured)

Controls: constant variables – stay the same to ensure your experiment changes are due to the IDV. Flower Example:

IDV:I am changing the amount of water DV: I am measuring the height Controls: same type of rose plant, type of water, time of

day, amount of light ….

Results

Quantative: numerical data Qualatative: Observational data

Organize all data in a chart by variables Concise and neat

Graph LINE or Scatterplots in science (mostly)

Category 1

Category 2

Category 3

Category 4

0

1

2

3

4

5

6

ABC

TITLE (should list both variables)

IDV (units)

DV (units)

Key

Label Axis and equal spacing

Conclusion

Results SUPPORT or DO NOT SUPPORT your hypothesis and why – refer back to your data.

Discuss results/analyze the data – use the numbers and graph to support your interpretation

Discuss bias or errors – what could have happened that could explain your results, besides your fantastic lab.

Scientific Law: accepted as true by all Law of gravity

Scientific Theory: An idea that is supported by lots of data but not necessarily accepted by all as true. Evolution