Hard boil eggs in a pot of water along with a tea bag. Invite preschoolers to brush away the stains on the egg "teeth." Show students how to brush all around the egg. Print and laminate large pictures of teeth. Let students use washable markers to draw cavities and stains on the teeth. Encourage preschoolers to use a toothbrush, water and toothpaste to brush the laminated teeth until they are shiny and white again.
Set up a dentist office in your classroom. Have preschoolers make a sign, arrange a waiting room and designate a chair or tabletop as a dentist chair complete with pillow. Provide a white lab coat or smock, toothbrushes, dental floss, dental mirrors, napkins and little paper cups. Invite preschoolers to line up stuffed animals or dolls that need a full checkup. Encourage preschoolers to take X-rays of each patient's teeth by drawing the teeth on a piece of paper. Use the napkins to keep the patient's clothes clean while preschoolers pretend-brush, floss and fill cavities on each patient.
Invite your preschoolers to create artwork for your classroom dentist office. Let preschoolers paint pieces of art using a toothbrush or dipping dental floss in paint and dragging it across the paper. Have your dentists-in-training draw large teeth and toothbrushes on sheets of butcher paper. Encourage preschoolers to add designs to their toothbrushes before decorating the dentist office walls. Help preschoolers shape modeling clay or salt dough into the shape of teeth. Allow the model teeth to harden, then have preschoolers paint the teeth white to make them shine.
Invite a local dentist or dental hygienist to visit your preschool class to talk about proper dental care. A great way to set up a classroom visit is by contacting your state or local dental organization as they have contacts for dentists that enjoy presenting to school groups. Your guest dentist can show students a model set of teeth, how to brush their teeth and even give preschoolers a starter kit that includes a toothbrush, pack of dental floss and a small sample of toothpaste.