Experimental Design Diagram
Title:     The Effect of Different Aged Compost on Bean Plant Growth 
Independent Variable:  Age of Compost
3 month-old compost
25 Plants
25 Plants
25 Plants
6 month-old compost
No compost (control
Hypothesis:  If older compost is applied, then plant growth will be increased.
Dependent Variable:  Height of Plants (cm)
Constants:  Amount of light
              Amount of water
                    Amount of compost
  • Based upon a rectangle.

  • Independent Variable:  written across top of rectangle that is divided into labeled columns to represent different levels of the independent variable.

  • Number of trials is indicated in each column.

  • Dependent variable and constants are also included in the rectangle.

  • An appropriate experimental title and hypothesis are written above experimental design diagram.