I think a person would be well-advised to read or see (I favour reading) "Twelfth Night" before seeing, or re-seeing "She's The Man". The movie is good on its' own, but comparing the two, and looking for the in-jokes makes it a lot more fun. Shakespeare was inspired by others. I think he'd give a thumbs-up.

Harld Bloom said in "Shakespeare, The Invention of the Human", that most of the people in "Twelfth Night" need to be locked up. Malvolio, the person Malcolm is based on, is-for no good reason. People in "She's The Man" are sane in contrast. For instance, Duke Orsino is far more leval than the Duke of Orsino. He also shows that a man can have feelings without being gay. He displays a lot of self-control.

It's a teen comedy (a clean one), so it doesn't have the dark edges of the play. For instance Olivia in the play is mourning the death of her brother. In the movie, she has been dumped.

If you like Sir Andrew and Sir Toby in the play, they don't have the same attention in the movie.

The in-jokes are quite often quick. The hairdresser Pauls' last name is given once. It is Antonio. Lots of people who've read the play say that Antonio has more love for a man than is just friendship. Deep love between men was noted in those days. Some see a sexual side to it-homosexuality was illegal.

The only line from the play I caught is where Duke Orsino quotes the coach on greatness during the soccar game. In the play, it is said by Malvolio, quoting Maria).