Name _________________________________
Writing a Hypothesis!
Date _____________________ Period _______________
A problem should be in the form of a question that requires an answer. This question should define the problem you want to investigate.
A hypothesis is an estimate or "educated guess" for solving a problem based on facts, observations, and available data.
It must be written in an “If, then, because” statement.
Example Scenario: A student wants to see if the amount of sunlight affects the growth cycle of a pansy. The student places one pansy on a window sill (natural light) and another in the living room (only artificial light).
Problem: Does the type of light affect the growth cycle of a pansy?
Hypothesis: If a pansy is placed in natural light, then it will grow two inches higher than a pansy grown in the
artificial light, because natural light provides more nutrients to plants than artificial light.
Directions
Create a problem and a hypothesis statement “IF, THEN, BECAUSE” for each of the situations below:
Situation 1
A NASA engineer wants to see if salt will reduce the amount of ice and snow buildup on the runway. She spreads 200 lbs of salt on a test runway and simulates an airplane landing by using test equipment. She then repeats the test on a runway without applying salt.
Problem: _____________________________________________________________________________________
_____________________________________________________________________________________________
Hypothesis: ___________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
Situation 2
An entomologist (bug scientist) wants to determine if temperature changes how many times a cricket chirps. He places crickets in a ventilated container inside an air conditioned room and crickets in a ventilated container on the patio. He makes observations for 5 days at the same times each day.
Problem: _____________________________________________________________________________________
_____________________________________________________________________________________________
Hypothesis: ___________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________
Situations 3
Stacey wants to see if the type of food affects the amount of birds gathered around a feeder. She places sunflower seeds, shelled peanuts cut in half, and corn. She makes observations at the same time for 1 hour each day.
Problem: _____________________________________________________________________________________
_____________________________________________________________________________________________
Hypothesis: ___________________________________________________________________________________
_____________________________________________________________________________________________
_____________________________________________________________________________________________

Practice with Variables
Question Independent Variable Dependent Variable
(Manipulated/Testing
Variable)
(Responding/Outcome
Variable)
Control Group
(controlled variable)
Constants
(factors that remain the same)
Does heating a cup of water allow it to dissolve more sugar?
Does fertilizer make a plant grow taller?
Does an electric motor turn faster if you increase the voltage?
Does the color of a candle affect the rate of a candle burning?
Who listens to music the most: teenagers or their parents?
Is a classroom noisier when the teacher leaves the room?
Do bicycle fenders keep the rider dry when riding through a puddle?