chain game
I played a game to see how energy transferred through the food chain by playing tag. There are three or more kinds of animals, cougars, plants, and deer. It is like taga and paper rock scissors. If a deer touches a plant, the plant becomes deer, cougars catch deer, and plants catch cougars (everything becomes part of the earth when it dies). Stop occasionally and tally what you are and you can graph it later. Kids like playing it, and it can lead to food chain, energy chain, etc...