Help! My own 3rd grader has been designated as "Scientist of the Week" and needs to perform an experiment on Friday. The teacher gave no recommended resources or ideas and I don't have time to scour the internet for a workable experiment. What science experiments have you elementary teachers seen which were good? It needs to be something which uses supplies we would already have at home. Oh, and the first scientist of the week did the Mentos in soda one already. Thanks!