The Cohen/Hoban first grade is acting out ""The Three Billy Goats Gruff"" for the whole school, and Paul is chosen for the troll while Jim is only a tree. In rehearsal, the slighted Jim is uncharacteristically obstreperous, until the understanding teacher suggests he play the river: ""You could hide under the blue cloth and move around so it looks like water."" But Paul is still mad at Jim--until the big day, when Paul freezes with stage fright. ""Nobody could think what to do. Then the river lumped up and said, 'Somebody is going over your bridge, Mr. Troll. They are going trip-trop, trip-trop.' 'Yes!' shouted Paul. 'Somebody is going over my bridge. . .'"" and the play is in gear. Readers are sure to empathize, and the first graders' old friends will enjoy seeing them all so endearingly costumed for the play.