In this video, the creator shows how he designed a chain reaction in which a tiny block topples a much larger one. Teachers may want to introduce the video using actual blocks. "How could we topple a large block (or a book) using a tiny block?" As students watch, have them observe how energy is being transferred as objects collide. They can then ask questions or define problems that involve engineering a chain reaction that shows energy transfer. Students could generate a list of variables that might affect energy transfer, such as the shape, weight, size, or orientation of the objects. From this list, they could generate testable questions and develop investigations. This video can stand alone or be used with the related resource OK Go Chain Reaction video. https://www.youtube.com/watch?v=qybUFnY7Y8w&list=PLF5563A1788629806&index=3