Students should work in pairs. Explain to students that they will be going out into the school yard to look for organisms, to see how different organisms change their surroundings, and to learn how these changes affect other organisms. Have them prepare a booklet that they can take with them outside, so they can write down and draw pictures of their observations. Once outside, students should look for at least five organisms (e.g., dandelions, grass, trees, various insects and spiders, worms and grubs, birds, squirrels, other students). They should try to determine how each organism changes its environment and how these changes affect other organisms (e.g., how they make it easier or harder for other organisms to live). For example, trees create shade and provide branches for birds to build nests; earthworms make dirt looser which helps plants to grow better. The students should put each organism on its own page in the booklet and draw pictures or use words to describe the changes they make and their effect on others. As a class, have students share what they found and learned. Students could give an example or two of their organisms and the class could come up with additional ideas of how it might make changes or affect others. If students found any organisms for which they couldn’t figure out how they changed their surroundings, the class could brainstorm ideas. Emphasize that all living things cause changes to their surroundings and these changes will have positive or negative effects (or no effect) on different organisms.