A Hypothesis
Written from a good testable question
Warm up: Review your notes on testable questions, and
write one testable question in the how does ______ affect
______ format.
Testable Question Review
v  A good testable question allows you set up an
experiment that will result in an answer.
v  A good testable question should allow you to
compare.
v  A good testable question should provide something
you can measure.
v  A good testable question doesn’t include words such
as “best” or “better”.
Testable or unclear?
v  Do fingers wrinkle faster in cold or hot water?
v  How does the temperature of water affect the rate of skin
wrinkling?
v  What do volcanoes look like?
v  This is not a good testable question, but does allow you to
make observations.
v  What laundry detergent will remove stains best?
v  How does the cost of laundry detergent affect stain
removal?
What about your warm up questions?
Are they good testable questions?
The hypothesis is a…
v  prediction of what will happen in an
experiment.
v  It is OKAY for a hypothesis to be
incorrect.
3 parts of a hypothesis:
v  IF – what you are testing (independent variable)
v  THEN – prediction of what will happen (dependent
variable)
v  BECAUSE – a good reason for the prediction
Practice
Given a good testable question, write a hypothesis in the IF,
THEN, BECAUSE format.
First Identify the 3 variables (independent, dependent, and 1
control).
Testable question: How does the volume of music affect short
term memory?
Independent: volume of music
Dependent: short term memory
Control: same music, same memory test
Practice continued
Testable question: How does the volume of music affect
short term memory?
IF
Independent: volume of music
THEN
Dependent: short term memory
Control: same music, same memory test
HYPOTHESIS:
If a person listens to music at high volume
then they will score lower on a short term memory test
because they will be more distracted than people
listening to music at low (or no) volume.
More practice
Testable question: How does the temperature affect the
molding of bread?
IF
Independent: temperature
THEN
Dependent: mold
Control: same bread, same conditions besides temp.
HYPOTHESIS:
If bread is placed at different temperatures
then bread at higher temperatures will mold faster
because warmer temperatures provide better mold
growing conditions (enzymes work better).
Write a hypothesis for the testable questions
v  1. Read the question carefully.
v  2. Identify the independent, dependent, and at least 1
or 2 control variables.
v  3. Write the if and then portions of the hypothesis by
including the independent and dependent variables.
v  4. Write the because portion of the hypothesis
including rational (a reason) for your prediction.
Testable Questions
v 
1. How does exercise affect heart rate?
v 
2. How does heart rate affect the amount of carbon dioxide the body releases?
v 
3. How does green house gas affect climate?
v 
4. How does the temperature of water affect the rate of skin wrinkling?
v 
5. How does the brand of soda pop affect the amount of carbonation?
v 
6. How does the cost of laundry detergent affect stain removal?
v 
7. How does soil type (sand, clay, top soil) affect plant growth?
v 
8. How does Influenza mutate to make so many new strains each year?
You identify the variables & write the if, then, because formatted hypothesis.
(8 x 6 parts each = 48 point assignment)