Science Activity: Ball Bearings

Get two cans (the kind with a deep groove in the rim, such as paint cans) and stack them. Turn one (still on top of the other) and notice the resistance (friction) you feel. Now sandwich marbles all along the rim between the cans. Place a heavy book on top and note how easily it turns around. Oil the marbles (you can spray them with cooking spray, but it is a bit messy) and the book turns more easily yet.

Science Activity: Simple Homemade Pulleys

Cut a wire coat hanger at the lower points (at the base of the triangular shape), and use the hook section to make your pulley. Thread both straight ends through a thread spool, crossing in the middle, and bend wire downwards to secure spool in place. Be sure the spool turns freely. Use hook for easy attachment.

The projects in these photos can be found in the Science Mastery Program on the Supercharged Science website:

Aurora Lipper is a real scientist, mechanical engineer, university instructor, airplane pilot, astronomer, and homeschool mother of two. She can transform toilet paper tubes into real rockets and make laser light shows from Tupperware®. Learn how to build catapults, pulley systems, and more by downloading the Simple Machine Experiments at

Copyright 2008 The Old Schoolhouse® Magazine.

This article originally appeared in the Spring 2008 issue of The Old Schoolhouse® Magazine. Reprinted with permission from the publisher.