Cherry (2010)

Ivy League Freshman, Aaron Milton (17) gets a different kind of education when he falls for Linda (34) a vivacious former wild-child who has returned to college to straighten out her life. The curriculum gets more challenging when Aaron meets Linda's sarcastic 14 year-old daughter, Beth - who quickly develops a crush on him. The math doesn't work in either direction but the dysfunctional triangle becomes a learning experience for all involved.