1. Scientific Method Vocabulary Terms

2. Your hypothesis should be written as an If…then…because statement.
HYPOTHESIS The part of an experiment where you make an educated guess or prediction as to what will happen.
Your hypothesis should be written as an If…then…because statement.
Example:
If fertilizer is fed to tomato plants then the plants will produce larger tomatoes because the fertilizer helps the plant grow and produce bigger fruit.

3. CONTROL Part of an experiment that is not being tested and is used for comparison. No independent variable is applied.
This is what you will compare the experimental tomato plant to.
It is what will go untouched.
Example
A tomato plant without fertilizer

4. VARIABLES Factors that can affect the outcome of an experiment.
There are 3 types of variables
constants
independent variable
dependent variable

5. Same amount of sunlight Same size and type of pot
CONSTANTS
The variable(s) in an experiment that are kept the same.
Examples
Same amount of sunlight
Same amount of water
Same size and type of pot
Same type of soil

6. INDEPENDENT VARIABLE
The experimental variable, or the variable that is changed or manipulated.
This is what you are testing, what you have control over. You can change or alter this variable in the experiment.
Example:
If fertilizer is fed to a tomato plant then the plant will produce larger tomatoes because the fertilizer helps the plant grow and produce bigger fruit.
The fertilizer is the independent variable. You have control over whether it is added or not. It is the variable you are experimenting with or that you can change. It is the independent variable.

7. Helpful Reminder
The independent variable is always part of the if portion of your hypothesis.
If fertilizer is fed to a tomato plant then the plant will produce larger tomatoes because the fertilizer helps the plant grow and produce bigger fruit.

8. DEPENDENT VARIABLE The variable that is effected by the independent variable.
This is the variable that you measure or observe during your experiment.
Example:
If fertilizer is fed to a tomato plant then the plant will produce larger tomatoes because the fertilizer helps the plant grow and produce bigger fruit.
The tomato size is the dependent variable. The size of the tomatoes is effected by the fertilizer. Tomato size is the variable you are measuring and observing during the experiment.
The fertilizer which is the independent variable may or may not effect the size of the tomatoes.

9. Helpful Reminder
The dependent variable is always part of the then portion of your hypothesis.
If fertilizer is fed to a tomato plant then the plant will produce larger tomatoes because the fertilizer helps the plant grow and produce bigger fruit.

10. DATA The information gathered and recorded
Example
A line graph showing the daily growth of the tomatoes or a bar graph showing the mass of the tomatoes

11. CONCLUSION The experimenter’s interpretation of the results.
What happened?
Example
The addition of fertilizer had no effect on the size of the tomatoes.