Mr. Earth (Paul Rudd) hosts Sesame Street's first "Earth-a-Thon." Abby, in an attempt to help Elmo be more "green," accidentally turns him the color green. When Abby has a hard time turning back, he begins to sing "It's Not Easy Being Green," until Mr. Earth convinces him that "It Can Be Easy Being Green." Telly, Rosita and Cookie Monster are volunteers standing by the pledge phones. After several hours, Cookie Monster can't bear not having eaten any cookies while taking calls, and eats his phone instead. As the 24-hour Earth-a-Thon comes to a close, Elmo and Abby have learned lots of different ways to "be green."