When Miss Fox shows up at school riding her bicycle, Mouse asks, "Do you have a flat tire?" "No," Miss Fox tells her students. "I am going green " Soon everyone in the class is working to keep the earth healthy. Mouse takes shorter showers (and does her singing after ); Bunny brings a cloth bag to the supermarket; and Possum turns the lights off when he goes out. And Miss Fox's simple act has ripples even beyond her own students...soon the whole school starts riding their bikes--including the principal.