Elmo and Abby find out it can be easy being green when they stumble onto the Earth-a-Thon, hosted by Mr. Earth, happening right on Sesame Street. Telly, Rosita, and Cookie Monster answer phone calls from children calling in with pledges to reduce, reuse, recycle (and possibly send cookies to Cookie). But what happens when Abby uses her magic to help Elmo be really "green"?