Ask a child to demonstrate how to use a flashlight. If nobody knows how, show the children how to operate it.
Place a stack of blocks or other familiar items onto the table with the whiteboard in the background.
Shine the light on the blocks toward the whiteboard and point out the shadow that is created on the whiteboard or desk when shining the light on one side.
Invite the children to take turns exploring or creating shadows with their hands and other objects. Have them trace some of the shadows on board.