Third Year Was a Secret for a Reason

A package of the seven Harry Potter books appear at Hogwarts during the Halloween feast during Harry's fifth year, with a note saying that the books were sent from the future and that everyone in Hogwarts, plus a few guests, need to read them. This is about Harry's third year at Hogwarts and is Hogwarts reading Harry Potter and the Prisoner of Azkaban. Also posted on ao3.