Many preschoolers garden right alongside the older family members. They typically understand that you bury a seed in the dirt and sometime later, a plant pops up. Use this activity to show your youngster what happens to the seed underground after you plant it, but before the little seedling pokes its head through the surface. Show your child how to make a tiny greenhouse out of a cup with cotton inside it to sprout some seeds. While the experiment works with just about any type of seed, children can enjoy eating their own radish, alfalfa and broccoli sprouts.
Fill a clear plastic cup about one-third of the way with cotton balls. Firm the cotton gently into place with your fingers
Dribble a little water onto the cotton moistening the surface. If you see water trickling into the cup's bottom, you added too much. Drain the excess.
Sprinkle sprouting seeds such as radish, alfalfa or broccoli on top of the cotton. Mist them with a little water from a plastic spray bottle.
Poke a few holes in the bottom of a separate clear plastic cup. This becomes the top of the miniterrarium. The holes allow air circulation around the seeds. Flip it upside down. Set it on top of the cup with the seeds and cotton in it forming an enclosure. Secure the cups together loosely with a few small pieces of masking tape.
Set the terrarium in a brightly lit, warm spot out of direct sun. The tops of your refrigerator or above a hot water heater are good locations.
Remove the terrarium cover every day to make sure the cotton remains moist. Spritz it with water if it begins drying out. The seeds begin sprouting in a few days.