Use a ruler to measure across the width and length of the base board to find the center. Mark the spot with a pencil.
Drill a hole through the base board, the diameter of the dowel rod, with the supervision of an adult. Insert the dowel rod into the hole and through the base board until it is flush with the back side of the base board. Use sandpaper to make the dowel rod slightly narrower, if necessary, to get a good fit.
Remove the dowel rod from the base board. Apply wood glue to the inside of the base board hole, and to the end of the dowel rod that goes into the hole. Insert the dowel rod into the hole until it is flush with the back side of the base board. Wipe off any excess glue with a rag. Allow the glue three or four hours to dry.
Slide one ring magnet onto the dowel rod and carefully hold the magnet until it reaches the baseboard. The ceramic coating on the magnets protects them, but the magnets can still chip if they're handled roughly.
Stack the rings on top of one another on the dowel rod, placing like poles facing each other. If the poles are not marked on the magnet, test by holding a magnet close to the magnet it will stack on top of. You can feel the magnets push away from each other when you have like poles facing each other.
Push down on the top magnet to feel the magnets repel each other. Let go and they will bounce up, appearing to float above each other.