Substituting materials is not suggested, but if something is not available, ask an adult's advice before using different materials.

  Note that each of the project ideas in Part II contains more than one exploratory experiment. The "Materials" section at the beginning of each project contains only the materials for the first experiment. Be sure to read through the entire project prior to starting to determine all the materials you'll need to complete each experiment.

PROCEDURE

  The "Procedure" section for the sample experiment contains the steps needed to complete the experiment. As described in Chapter 2, a variable is anything that has an effect on the experiment. In the sample experiment, water and soil are tested to see which surface warms faster. The type of surface being tested is the independent, or manipulated, variable. Each surface absorbs a certain amount of heat from the lamp. The resulting change in temperature of each surface is the dependent, or responding, variable. All other variables, such as the amount of light that the surfaces receive, the amount of water and soil tested, the containers for the test materials, and, generally, the total environment around each container (room temperature, humidity, etc.), are the controlled, or constant, variables. Note: Approximate metric equivalents have been given after all English measurements.

Figure 6.5 Table and Bar Graph for Sample Experiment