1. Writing a Good Hypothesis
If…Then…Because
Writing a Good Hypothesis

2. An “If… then…because” statement in a hypothesis tells the readers what you believe will happen in an investigation when something is changed, so you can see the effect of the change.
A Good Hypothesis

3. IF…tells the readers what will be changed
IF…tells the readers what will be changed. This is the manipulated (independent) variable in the investigation.
IF…

4. THEN… tells the reader what will happen because of the change (manipulated variable) described in the If… statement. This is the responding (dependent) variable in the investigation.
THEN…

5. BECAUSE… tells the reader how you know this will occur
BECAUSE… tells the reader how you know this will occur. It should be based on something you have experienced, or perhaps something you infer.
BECAUSE…

6. Constant variables are quantities that a scientist wants to remain constant, and he must observe them as carefully as the dependent variables.
Constant Variable

7. If 7th graders and 8th graders complete the same math problems, then the 8th graders will have more answers correct, because they have studied math for one year longer than the 7th graders.
If dry bread and moist bread are left in bags for two weeks, then the moist bread will grow mold more quickly than the dry bread, because mold is a living organism, and organisms need water to survive.
If some students eat breakfast before school and others do not, then the ones who do eat breakfast will have better grades in their morning classes, because their brains have more energy to think.
Examples

8. An experiment designed so that changes to one item cause something else to vary in a predictable way.
Example: You should brush your teeth often so you don't get cavities.
Cause - You should brush your teeth often. 
Effect - You won't get cavities.
Cause always happens first, effect happens second (or after the event)
CAUSE and EFFECT

9. An experiment must have measurable values for each variable
 An experiment must have measurable values for each variable. Weight or mass is an example of a variable that is very easy to measure. Something like love, can not be measure.
MEASURE

10. DRY MIX D = dependent variable R = responding variable
Y = graph information on the vertical or y-axis
M = manipulated variable
I = independent variable
X = graph information on the horizontal or x-axis
DRY MIX