Coolest. Science. Project. EVER.
Stole this idea from Miss Julie, my beloved girlie and the coolest First Grade teacher in North America.
The twins and I tried this last Fall–simply open up a pumpkin–get a sturdy variety like Iron Man or Alladins. Fill 3/4 with soil and water sparingly. Too much and your little ecosystem gets mushy. The seeds inside will root nicely and start sprouting green tendrils. In Spring, plant the whole thing outside and repeat the process next Fall. There’s an excellent guide to pumpkin varieties here.