My idea - Each child decorate a hand and attach it to the big tree. (Make paper hand cutouts from your children's hands. Write things they are thankful for on the hands and you will build your own thankful tree!
Given the question of apples will float or sink, students will be able to vote which one they agree with. Given apples, students will be able to put the apples in the bowl of water and determine if they will sink or float.