Wise Guys Prefer Brunettes(1926)

The crotchety dean of Pinkham University blames the "bad behavior of the school's female students on a dress shop owned by Helene, and informs her he's shutting her shop down. Meanwhile, her boyfriend Napoleon has invented a plaster that restores youth. The dean accidentally sits on the plaster and reverts back to his younger days when he himself used to chase college girls. Complications ensue.