Homeschool Middle School Physics Lab: Simple Harmonic Motion (Ages 11-13)   

The Science of the Swing! Nature is full of cycles—from the beat of a heart to the swing of a playground set. By experimenting with pendulums, students investigate the variables that control "rhythmic motion."  This lab introduces the concept of a "variable," teaching students how to isolate one factor at a time to find the true cause of a physical change.