Here's the part I don't get. They make a big deal about how there are so many rules set up to protect the students. The teacher isn't supposed to talk about the dark magic because someone might get hurt. That same teacher turns a student into a ferrit and is repremanded because you're not allowed to morph the students. Snape has a truth potion he tells Harry he wants to use on him but he can't because the rule is you can't use it on students. Rules rules rules, all to keep the kids safe. Oh, but wait a second... Then there's this big tournament that's really really dangerous and life threatening, and in fact students have died in it in the past, and you'll be chased by a dragon that tries to eat you and attacked by mermaids that try to drown you and strangled by weeds and dragged underground to suffocate -- and the teaching staff encourages the students to participate! Does this make any sense? I'm sure it's probably explained perfectly in the book, but in the movie it's just plain bad storytelling.