Charlie, Jeffrey and Sidney are all in the seventh grade and all are spending too much time in the principal's office. Charlie talks nonstop, Jeffrey is too frightened to talk at all and Sidney would much rather let his fists hold up his end of the conversation. One day all three end up before Mr. Duncan, or Frog Face, as they call him behind his back. Finally realizing that detention is not solving the continued problems, Mr. Duncan decides that what these troublemakers need is some discipline and order, and consigns them to a series of lessons in karate run by his son Willie. What begins as a penance slowly becomes bearable and then a pleasure for the three boys, as they all begin to learn something about themselves and how to get along with others.