Place one in open plastic bag and pin to a bulletin board. Place second green leaf in sealed plastic bag filled with water to cover plant. Then, freeze the water-covered leaf in refrigerator. Science is both facts and process. Scientists make observations.
Hypothesis is a scientist's educated guess about an observation.
Gather information about guess. Write a hypothesis for the observations you have gathered. Test your guess with an experiment. Explain your answer. Student will review and observe each leaf weekly.