The purpose of this PowerPoint is to
present strategies to aid students at
the high school and introductory
college levels to:
 Design experiments
 Write procedures
 Construct tables and graphs
 Generate ideas
 Write simple lab reports
Title :
The effect of ...IV... on ...DV...
Hypothesis : If the ...IV... is modified in this way,
then this will happen to the ...DV...
Independent variable:
these boxes
show how the
IV is modified
_____trials
_____trials
Dependent Variable:
Constants:
Control:
_____trials
_____trials
_____trials
Title : The effect of different aged compost on bean
plant growth.
Hypothesis : If older compost is applied, then plant
growth will be increased.
Independent variable: Age of Compost
these boxes
show how the
IV is modified
3 month old
compost
6 month old
compost
No compost
# trials
25 trials
25 trials
25 trials
Dependent Variable: Height of plants (cm)
Constants: amount of light, water,
Control: no compost
compost
Q1 – What materials are readily available for
conducting experiments on ____________
Q2 – How do ______ act?
Q3 – How can I change the set of ____
materials to affect the action
Q4- How can I measure or describe the
response of ____ to the change?

What materials are readily available for
conducting experiments on plants?
Soil
Fertilizer
Water
Light/heat
Containers

How do plants act?
Grow
Wilt
Flower

How can I change the set of plant materials to
affect the action?
Water – amount, method of application, source, pH
Containers – location of holes, number of holes, shape,
material, size
Plants – spacing, kind, age, size

How can I measure or describe the response
of plants to the change?
Count the number of leaves
Measure the length of the longest stem
Count the number of flowers
Determine the rate of growth
Mass the fruit produced

Things to consider when constructing a table
 Does the system communicate the relationship
between the IV and DV?
 Does the system communicate the order in which
the IV was changed?
 Does the system’s title communicate the purpose
of the experiment?
 Are the units of measurements communicated?
DISCRETE DATA –
CATEGORICAL OR COUNTED (DAYS
OF THE WEEK, GENDER, COLOR)
CONTINUOUS DATA
MEASUREMENTS INVOLVING A STANDARD
SCALE WITH EQUAL INTERVALS;
CONTINUOUS RANGE OF MEASUREMENTS
The effect of coloration on the
number of kittens sold at a
pet store
The effect of concentration of
sugar water on the number of
visits of hummingbirds to a
feeder
The effect of the horsepower of a
tractor on the mass of a sled it
can pull