Many people are also worried that he'll take the magic out of Hogwarts by letting the children wear casual (or Muggle) clothes.
Cuarón is only trying to bring his own blend to the movies, and this may change when a new director comes in for the fourth film.
Besides, I would hate to have to wear my school uniform everyday of the year!
Cuarón has already made a film of a classic children's book - The Little Princess, so he will have experience putting The Prisoner of Azkaban on the screen.
I'm looking forward to seeing Michael Gambon as Dumbledore, and Gary Oldman as Sirius in the film.
I'm going to keep an open mind about it all."
Anthony, 15, Glasgow
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