Love Don't Cost a Thing (2003)

Science nerd Alvin Johnson (Nick Cannon) is proficient at engineering but incompetent when it comes to dating. One day, popular girl Paris Morgan (Christina Milian) appears at the auto shop where he works after school. She has damaged her mother's car and urgently requests repairs. Alvin offers a bribe: He will fix the car immediately in exchange for two weeks of dating. Paris agrees, and Alvin is able to enter the sacred realm of the popular kids. But at what cost to himself?