Variables

A variable is a factor that changes and may affect the results of the experiment. Plan every experiment so that it is testing only one variable at a time. During the experiment, all other variables should be controlled variables.

The independent variable is the variable that you will change or manipulate. During the experiment, you will observe the effect that changing your independent variable has on the variable you are measuring

The remaining variable is one that is being tested; this is called the dependent variable. This is the variable that you will observe and/or measure in the experiment. The effect on this variable depends on the changes you have made to the independent variable.

To write a clear method or procedure for your experiment, you need to determine how the independent variable, the dependent variable and the controlled variables will be monitored and measured.