By definition the control in a science experiment is a sample that remains the same throughout the experiment. The control must remain the same or equal at all times in order to receive accurate results. You can have as many controls as necessary to achieve results.
Graphs are often an excellent way to display your results. In fact, most good science fair projects have at least one graph. For any type of graph: Generally, you should place your independent variable on the x-axis of your graph and the dependent variable on the y-axis.
Telling a Story With Graphs. Task. Each of the following graphs tells a story about some aspect of the weather: temperature (in degrees Fahrenheit), solar radiation (in watts per square meters), and cumulative rainfall (in inches)) measured by sensors in Santa Rosa, CA in February 2012. Note that the vertical gridlines represent the start of the day whose date is given.