This unique St. Patrick’s Day activity will be a memorable hit with preschoolers.

Children can find the rocks hidden by a grown up (Leprechaun) who made the rocks a day in advance from baking soda and water. The Leprechaun will hide a gold play coin in each rock. Children will find the hidden magic rocks and “rinse them” in a bowl of vinegar.

The chemical reaction of vinegar and baking soda will cau…