1. The Fair Test
Lesson 4:
January 26th, 2011

2. Observation vs Inference
Information gathered with the 5 senses
Sight
Smell
Touch
Taste
Hearing

3. Observation vs Inference
Guess or assumption based on observations, previous knowledge and experience

4. Examples
For the Following pictures make 2 observations and 2 inferences for each picture.

5. Examples Observation Inference - The man is pulling a box
- The box is heavy
- We infer this because the man is sweating.
- The man is sweating
The man is thinking about how heavy the box is
We infer this because his eyes are drawn like he is thinking.

6. Examples Observation Inference - The man is watching a computer screen
- The man is scared
- The man is chewing his finger nails.
The man is nervous

7. Examples Observation Inference - The woman is clicking her heels
- They are on vacation
- They are carrying a camera and suitcase
They are happy

8. Examples Observation Inference They are in costumes -It is Halloween
-They have bags that say trick or treat.
They have candy in the bags.

9. Review of Fair Tests and Variables
Fair Testing
Are the following tests fair or not fair? Why or why not?
Which ice is faster for Cheechoo to skate on?
Fair– The skater is the same, only the ice is different.

10. Which ball will bounce higher?
Not fair – (2 variables) The balls should be dropped from the same height.

11. Which Coffee has more caffeine in total?
Not fair – The brands of coffee are different and the size of cup is different.

12. Only one thing can change at a time
What makes some of these tests not fair?
Only one thing can change at a time
How many variables can you change and still have a fair test?
ONE

13. Activity
With a partner, pick a problem that you would like to test and think of a way to make a fair test. Include all the steps necessary for a fair test. Be very specific and be sure to include the independent variable, dependent variable, and controls. You may need to look back in your notes to see what the steps are to the scientific method. When you are done, be sure to show Mr. Hoover your work.