Not Another Teen Movie actually worked I thought. Maybe it's because I had seen so many of those movies, maybe it's because it actually stayed on track and parodied only what it was supposed to and just be generally funny everywhere else. It didn't insert "current" things for quick jokes, it was just good. The first Scary Movie was good too, second took it downhill, and then from there it just got retarded and doing things it had no business doing simply because everyone involved wanted more money.
They need to be told to pick a style (or movie) to spoof, and stick with it, don't insert current events to make it funnier, don't insert things from other movies or other genres to make it funnier, just focus on what it is you're spoofing and leave it at that. That's what made all the best spoof films what they are, focus. If this had just been a spoof of 300 with some funny bits in there that didn't involve cheap jokes and refrences to other things that have no business in the same world as 300, it might have had a chance.