David and Goliath
I have a great book called Fun Science that Teaches God's Word by Susan Martins Miller, published by Cook Ministries. One lesson is called "Spread the News".
Volunteer Moderator Carol notes: ISBN-13: 9780781440813
The poster (Stacia) then included in this post a portion of the book that covered this lesson. This has been removed due to copyright issues.
Basically the lesson involves a newspaper and a ruler. Refer to this science demo done for a lesson on the Walk to Emmaus here (Scroll down to the Old Science lesson and look at the portion that starts at "Say: Here’s another experiment. Place a ruler on the table..." and goes until "No wonder it wouldn’t budge."
You may be able to get paint sticks from local home/paint stores, and try the project with them first. That way, each kid can try the experiment on their own.
We may be weak (like the newspaper), but God is there to care for us. And when we see God' power in action, we can't help but be amazed.