I actually liked this movie.
I seriously did. Not the best film ever, obviously, but very underrated.
I know people have different tastes, but it's blatant that alot of people that rated the movie a '1' haven't even seen it. Sure, it's not the best movie ever made but it does NOT deserve a one. It's better than a majority of the crap made nowadays.
And what you've got to remember is that ultimately the movie was made for kids. I personally think it's a film for all the family to enjoy but I think kids (who are the target audience!) would love it.
So I just don't see what everyone's problem is. You're not the target audience.
Sure it's a bit over exaggurated at times (mainly when Melanie's with her friends) but that's whats funny. The writers obviously wrote it so it would mock the 'typical teenager' - it's not serious.