Make a tree about two feet high out of construction paper to put on the bulletin board. Close to the door so that is visible when parents enter the classroom. Label the tree "Our Giving Tree".
Make apples and write on each apple something that the class may need during the school year that the school does not provide. (glitter, feathers, zip lock bags, Kleenex, snacks, etc.) At open house or orientation parents are then invited to take an apple and send in the needed supplies.
Also, on a chart paper write: Thank you for taking an apple from our giving tree and contributing to our classroom. In case the parent did not hear the explanation of the Giving Tree.