TV’s Jerry Seinfeld, and his neurotic, self-absorbed pals, Kramer, George and Elaine make their exit in an episode that’s not about “nothing” but is about an important environmental issue. Here to explain the plot line to Steve Curwood is Kenny Byerly, a senior at Foothill High School in Pleasanton, California who won an essay contest of the group Zero Population Growth by writing this fictitious Seinfeld episode.