Whatever floats (or sinks) your boat.

Get Ready: Find six or eight everyday objects from around your home: small rock, screw, pencil, plastic toy, cookie cutter, etc. (The best stuff is in the junk drawer.)

Get Set: Set out two small bowls and one large one. Fill the large one about half full of water.

Sit Back and Watch Your Child Go: With one small demonstration from you, your child will know to place the objects in the water, and then remove them, placing the objects that sink in one small bowls and the ones that float in the other.

As your child grows: Amp up the learning on this simple exercise: Give him kitchen tongs to use when picking up the items. Ask him to predict whether an item will sink or float. Teach him the meaning of the word “predict.” Give him more responsibility by storing the “sink or float” bowls down where he can reach them. (That way he can get the bowls out by himself, and complete his exploration by drying the bowls and putting them back where they belong.)

Your child will love: The different containers; the interesting objects; observing the sink and float; using tongs; finding other things around the house to try for sink or float; knowing a grownup word like “predict.”