The Faculty (1998)

"The Faculty" is the 1998 sci-fi horror film about high schoolers in a small town who realize their teachers are being taken over by an alien parasite. Famke Janssen plays school nurse Rosa Harper, one of the infected staff, and appears in a nude scene tied to the character's true form. Laura Harris plays Marybeth, the new student at the center of the film's final twist, with a scene of her own included here. The site carries 2 scenes total from the movie, split between the two actresses.