```During a six week study, one tank of fish is
fed once a day, one tank of fish is fed twice
a day, and another tank is fed four times a
day. The fish’s weights are recorded daily.
&copy; 2015 Tammy Morehouse
Name two variables that would need to be
controlled in each fish tank.
Three different hives of
bees were allowed to exit
their hive and collect pollen
at different times of day.
At the end of a month, the
amount of honey produced is
measured.
What is the dependent variable in this
investigation?
&copy; 2015 Tammy Morehouse
One sunflower pot is watered
with pure water and 3 others
are watered with increasing
concentrations of salt water.
The height of the sunflowers is
measured weekly.
What is the independent variable
in this investigation?
&copy; 2015 Tammy Morehouse
Different groups of 7th graders were timed on
a math test. One group was allowed to use
calculators and one was not. What was most
likely being tested in this investigation?
a.
b.
c.
d.
Battery life of the calculators
If students knew how to use calculators
If students with calculators could solve
problems faster
If 7th grade students were smart enough
to solve the math problems
&copy; 2015 Tammy Morehouse
Sherry believes that if cats
are fed organic pet food,
they would be happier.
Is Sherry’s hypothesis
testable?
Why or why not?
&copy; 2015 Tammy Morehouse
Two students wanted to find out which of their
toy race cars would go the farthest. They let
each car roll down a ramp and then measured
how far the cars rolled.
The
The
The
The
height of the ramp
weight of the ramp
length of the cars
shape of the cars
Which of these should be held constant if they
want a fair test of their cars?
a.
b.
c.
d.
&copy; 2015 Tammy Morehouse
A student is attempting to identify an unknown
liquid. She places 10 mL of the liquid in a test
tube and begins heating it over a burner.
She checks and records the
temperature every minute
until it begins to boil.
What is the independent
variable?
&copy; 2015 Tammy Morehouse
Students in a biology class thought that salt
water would affect the movements of planaria.
They put 25 planaria in salt water and
recorded their observations.
Which flaw was present
in the design of their
experiment?
&copy; 2015 Tammy Morehouse
Students who like
jelly beans
145
Students who do
not like jelly beans
Rhonda believes that most students like jelly
beans. She takes a poll of the 8th grade class
and records her results. Based on her data, she
believes that her hypothesis is correct. Is her
conclusion valid? Use numbers to support your
157
&copy; 2015 Tammy Morehouse
1st
11
2nd
10
3rd
7
4th
5
5th
1
6th
A bird feeder was placed in the school yard.
Students from each science class recorded the
number of birds who visited the feeder. The
next day the teacher shared the results with
the class. What conclusion can be made from
the data?
15
&copy; 2015 Tammy Morehouse
Johnathan plants seeds at
varying depths. He measures
the growth of the plants
over the next few weeks and
records his data.
What is the independent
variable in this investigation?
&copy; 2015 Tammy Morehouse
A student wants to know whether giving dogs
toys makes their tail wag more. He gives one
group of dogs toys and one
group of dogs he does not give
toys. He counts how many
times each group of dogs tails
wag in a given amount of time.
What is the control group
of this investigation?
&copy; 2015 Tammy Morehouse
A student believes that ducks
swim faster when they are
in cold water. He tests two
groups of ducks, one in cold
water and one in warm
water.
What will the student be measuring
(dependent variable) in this experiment?
&copy; 2015 Tammy Morehouse
A student wants to know if the amount of water
Is this a testable
question?
Why or why not?
&copy; 2015 Tammy Morehouse
&copy; 2015 Tammy Morehouse
Mrs. Williams believes that if she gives
students peppermints during the test that
they will perform better.
During the next test she gives
half the class peppermints and
half the class she does not.
What is the independent variable
in her experiment?
Amanda wants to
know what the best
time of day is to
catch fish.
She goes to Hedgehog Pond in the morning and
fishes for 4 hours. She then goes to Three Creek
Pond in the afternoon and fishes for 4 hours. Has
Amanda conducted a fair experiment? Why or
why not?
&copy; 2015 Tammy Morehouse
Hayden was investigating how much water
different brands of water balloons could hold.
He filled up one balloon from each brand and
measured how much water it held until it broke.
What could he have done
in his investigation to
improve his results?
&copy; 2015 Tammy Morehouse
A recent study found that there is a direct
relationship between the amount of exercise
students engage in and their academic
performance.
What was the
dependent variable
in this study?
&copy; 2015 Tammy Morehouse
Lorna wants to know if the size of the cookie
influences how long it takes to bake. She places
differing amounts of cookie dough on baking
sheets and times how long it takes for the
What is the independent
variable in her investigation?
&copy; 2015 Tammy Morehouse
A medical company has developed a new anti-itch
cream. In order to test how well it works, they
give one group of rash sufferers
the cream with the medicine and
another group of rash sufferers
a cream without the medicine.
What is the control group of this
study?
&copy; 2015 Tammy Morehouse
Alice wrote down four ideas about earthworm
behavior that she wanted to test. Which idea
can be tested experimentally?
a.
b.
c.
d.
Earthworms like the taste of
dirt better than sand.
Earthworms are happier in
black dirt than red dirt.
Earthworms exist to decompose
decaying materials.
Earthworms will move away
from direct light sources.
&copy; 2015 Tammy Morehouse
Sara wants to investigate which type of citrus
juice works best at keeping apples from turning
brown. She uses lemon juice, lime juice, and
orange juice.
She places one type of juice on
different apple slices and times
how long it takes for the
apples to brown.
What is the independent
variable in her experiment?
&copy; 2015 Tammy Morehouse
Michael believes that the shape
of paper airplanes affects how
far they will travel.
Name two variables that he will need to keep
constant in order to test his hypothesis.
&copy; 2015 Tammy Morehouse
Billy believes that the type of music students
listen to affect their heart rate. He separates
students into groups and have them listen to
rock, country, hip-hop, and pop music.
He records each students heart
rate before, during, and after they
listen to the music.
What is the dependent variable
in his investigation?
&copy; 2015 Tammy Morehouse
```