Huff pulls the train. Puff pushes the train. Day in and day out, the train clicks and clacks down the tracks. But one day, Huff and Puff decide to trade places. Will the train come to a hault Or will the caboose and the engine find that the grass isn’t necessarily greener on the other side of the tracks Simple rhyme and easy to read verse will help beginning readers build their vocabulary and strengthen reading skills.