I made it about halfway through this movie, and at that point realized that I absolutely didn't care how it ended. It is basically a bland teen comedy that I only watched because I like Helen Mirren, who is in fact very good as an impossibly cruel teacher.

The basic idea of the movie (or let's say the first half of the movie, since I don't know - or care - how the second half goes) has been done before, most notably in 9 to 5, and a comparison between the two shows how thoroughly Tingle gets it wrong. You need to feel things are spiraling out of control in a way that makes you feel events are inevitable, and you need well-defined, interesting characters who you care about, and you don't have that. Not the worst movie I've ever seen, but it never grabbed me for a second.