This is a SIMPLE activity to teach your students the basics of experimental design and how to distinguish between independent, dependent, and constant variables. Prepare them for Planning and Carrying Out Investigations in your class this year or use this as a last-minute sub-plan. This is a pdf document that links to a google document version of the activity.* Student handout* Teacher document with key and teaching tips.* Link to a google document version that can be used directly in google c