Experimental Design Vocabulary List
Experimental Question – A testable question that asks how a change you make might affect the results or what happens.
“If we change this.... does it affect that?”
Hypothesis – What you expect to happen to the results based on the change you will make and
other evidence you have gathered.
Variables – Anything that could change during an experiment that might affect the data and results.
Dependent Variable – What scientists measure to see if it has changed during the trials. This becomes your data f
or the experiment.
Independent Variable – The variable that is being tested. Scientists carefully change it on purpose to see the effect
it will have on the data and results.
Controlled Variables – All the other variables that are kept the same to be sure that they do not have any effect.
This makes the experiment a fair test.
Procedure – Step by step directions for how to run a set of trials. Each trial gathers one piece of data
and observations
Control Group – A set of trials where the Independent Variable is NOT being changed and tested.
Experimental Group – A set of trials where the Independent Variable IS being tested. The I.V. is changed on purpose
and the results are then compared to the control group.
Data Table – A chart for recording and organizing the data and calculations.
Graph – The data presented in visual form using bars or lines.
Data Analysis – Objective, mathematical thinking about the data.
Observations – Objective Statements about what scientists noticed during the trials. Can be used as evidence.
Conclusions – Subjective thinking and analysis of the results. What scientists think about the results of the
experiment.
Repeatability – The ability for other scientists to follow a procedure and get similar results.
