The criticism is a little exaggerated.
The only thing I can say is that it wasn't scary. The Ripper wasn't a menacing villain, he looked like Rob Zombie.
But other than that, it is not as awful as people are making it out to be. For one, the first 15 minutes are very good. The film starts off with things happening right off the bat and when we move to the 16 years later portion, we get the always-fun "kids gather to tell urban legend" scene which was pretty entertaining.
The murders were not scary or even that creative, but there's more to like other than the uninspired kills.
Fang was a well-written character. So evil and downright cold, you want to punch her in the face. But then her character does a 180 later on and we see why she is this way. And her school clique was like a take on Heathers or something, without all the Valley Girl talk.
Bug putting his cell phone in the girls' bathroom was a pretty amusing sequence.
Brittany and Brandon's walk through the woods had a nice Halloween-time feel with the dead leaves and the location.
I loved the confrontation between May and Fang over the rocking horse. May really tells her off and it was a great scene as well as the follow-up with Fang beating up Bug--intense and emotional stuff for a slasher movie.
The finale seemed to lag and was a bit of a letdown, I will admit.
Overall, it was not a great movie but it did have great -moments-, and with a little more work on the scare factor and the murders, it could have been something terrific.
But to see people compare it to SyFy movies or act like it was THE worst film "like, ever made" is ridiculous. You can just say "It was disappointing" and be honest about it rather than use exaggeration to the point of abuse. You don't have to label it the worst film of all time to get your point across to people.