A few days before the championship girls basketball game between Franklin High School and Center City High, Susan Adams, Franklin's star player, is suspended. According to the terms of an old eccentric's will, the school must win the game in order to receive an endowment for a new gymnasium, and consequently, Susan is replaced by newcomer Genevieve Rogers, an expert player. Genevieve soon earns Susan's enmity when her talent on the basketball court wins her acclaim as well as the attentions of Bill Kennedy, the most popular boy at Franklin High. One day, Dr. Wright, the school principal, who is secretly collaborating with Aloysius, a brilliant science student, to develop new formula for fuel, asks his secretary, Gloria Martin, to obtain some chemicals from Genevieve's father, the town pharmacist. When Genevieve overhears the conversation between Gloria and her father, she misunderstands the context and thinks that Gloria is trying to extort money from him. Soon after, racketeers Harding Jones and Marmaduke Green come to town and use high school student Smiley as an unwitting conduit to set up bets with his fellow pupils. Soon, Bill is placing bets in order to win enough money to hire bandleader Al Donahue to play at the school party, and Genevieve is betting in order to win enough to "pay off" Gloria. Planning a big haul, the racketeers bet against Franklin and then use Susan to make it look like Genevieve has accepted a bribe for losing the game, thus insuring her suspension from the team on the eve of the big game. All ends happily, however, when Genevieve's name is cleared at the last minute and she wins the game for Franklin. Genevieve then is relieved to find that her father's relationship with Gloria is strictly business when Dr. Wright and Aloysius finally demonstrate their formula. After Al Donahue offers to perform for free at the school party, the students celebrate their victory and Genevieve forgives Susan.