You will need 3 apples of the same size. Chop 1 into tiny pieces and set aside (including skin), peel one and set aside (save skin), and leave one whole. Students will predict which apple will lose the most mass over a period of one week. This activity can be done whole class and then used as an independent science center. After on week, compare the 3 apples using a scale and bears. You may use actual grams if this activity is used with older students. This is such a fun activity and gets the kids looking forward to each days science/math time.