Never Been Kissed (1999)

A copy editor in her early twenties gets her chance to become a reporter at a Chicago daily. Her first assignment consists of a feature on what cool high school students are doing. In order to uncover the life of the hip high schoolers, she must go undercover as a student herself. Meanwhile, her slacker brother decides to go back to the same high school in hopes of getting a second chance at being noticed by major-league baseball scouts.