Also on these boards
A volcano in a mug. Neat idea to show kids how they work. Much more accurate than the old baking soda/vinegar idea.
The Pumpkin Project from Growing in Pre K. Open a pumpkin, add soil & water & watch the seeds already inside the pumpkin grow. Also links to other activities to teach about & observe the pumpkin life cycle. Recommends reading the book "Pumpkin Jack" several times during this process.