Science experiments perfect for Autumn

Fossils

1 1/2 c. flour, 1 c. used coffee grounds, 1/2 c. salt, 1/4 c. sand, 1 c. water

Figure out what you want to use as artifacts...  Plastic Dinosaurs, coins, vegetation or anything you can think of, really!  

Mix the flour, coffee grounds, salt, sand, and water together. 

Form the mixture into round, flat balls. Press an "artifact" firmly into each ball then carefully remove it to reveal an impression. 

Place the balls on a cookie sheet lined with waxed paper and bake for 20 minutes at 150 degrees F.  The balls will shrink slightly but when they are cool and hardened, the fossils are ready. 

You can also hide "artifacts" inside the balls and the kids can use a small hammer to break it open and discover the hidden treasure inside.  Fun for discovery type birthday parties!

Jumping Penny

Put an empty glass bottle in the freezer overnight. Take the bottle out of the freezer and quickly put a penny over the mouth of the bottle. Hold both of your hands tightly around the bottle. The penny should begin to jump up and down because the heat from your hands flows through the glass and warms up the air inside the bottle. As the air gets warmer it expands, pushing up on the penny and making it jump.

Oobleck

1 c. water, few drops of food coloring, slowly add 2c. cornstarch.

Oobleck: A mysterious matter that kids can shape into balls or let ooze from their fingers. Referencing Dr. Seuss for this one and there is a great tutorial online at:
http://www.instructables.com/id/Oobleck/
  So much fun, you have to try it!