ANSWER KEY
Practicing the Scientific Method
PART I. Read each of the scenarios below and then identify the items listed for each one.
1. Most scientific experiments/studies start with OBSERVATIONS which lead to AN INVESTIGATIVE QUESTION.
2. In this class, we use what two formats to write an investigative question (IQ)?
HOW DOES THE iv AFFECT THE dv?
WHAT IS THE EFFECT OF THE iv ON THE dv?
3. The investigative question identifies the INDEPENDENT VARIABLE (IV) and the DEPENDENT VARIABLE (DV).
4. Another term for independent variable is MANIPULATED VARIABLE
5. Another term for dependent variable is RESPONDING VARIABLE
6. The independent variable (manipulated variable) is the one you CHANGE. The dependent (responding
variable) variable is the one you MEASURE.
7. Create a rhyme that helps you remember the difference between the independent and the dependent
variable. Write this rhyme here:
LET’S HEAR THEM!!!
8. Controlled variables (NOT THE CONTROL) are the variables you need to hold CONSTANT.
9. Once you have identified the purpose of your experiment (also known as your INVESTIGATIVE QUESTION), you
should do some RESEARCH so you can write your hypothesis, because everyone knows that a hypothesis is an
EDUCATED GUESS.
10. In this class, we use what format to write a hypothesis (Hypo)?
IF THE IV IS CHANGED IN THIS WAY (INCREASED TO… OR DECREASED TO… OR THIS BRAND OR THAT TYPE) THEN
THE DV ?
11. What is the next step in the scientific method after the hypothesis?
PART II. Read each of the scenarios below and then identify the items listed for each one.
Scenario 1: Lemon Trees receiving the most water produce the largest lemons.
Identify the following:
 a possible independent variable (IV) ______________________________________________________
 a possible dependent variable (DV) ______________________________________________________
 an investigative question (using the correct format)
______________________________________________________
 at least three controlled variables ______________________________________________________
 a possible hypothesis (using the correct format)
______________________________________________________
Scenario 2: People who have pets tend to have decreased blood pressure.
Identify the following:





a possible independent variable (IV) ______________________________________________________
a possible dependent variable (DV) ______________________________________________________
an investigative question (using the correct format)
at least three controlled variables
a possible hypothesis (using the correct format)
Scenario 3: Music makes a plant grow taller.
Identify the following:
 a possible independent variable (IV) ______________________________________________________
 a possible dependent variable (DV) ______________________________________________________
 an investigative question (using the correct format)
 at least three controlled variables
 a possible hypothesis (using the correct format)
Scenario 4: The more hours you spend on Snapchat the lower your grade in science.
Identify the following:
 a possible independent variable (IV) ______________________________________________________
 a possible dependent variable (DV) ______________________________________________________
 an investigative question (using the correct format)
 at least three controlled variables
 a possible hypothesis (using the correct format)
Scenario 5: The amount of time spent bingeing on Netflix the fewer friends I have.
Identify the following:
 a possible independent variable (IV) ______________________________________________________
 a possible dependent variable (DV) ______________________________________________________
 an investigative question (using the correct format)
 at least three controlled variables
 a possible hypothesis (using the correct format)