trying to find the name of this movie!!

[dava]

please help me im trying to find out the name of  a movie. All I can remember about it is these people went to a high school reunion and this man goes crazy and kills people. He also wore a bag on his head. It's kinda like the movie clue but thats not it. It's an older movie like in the 70's or 80's. I think its supposed to be scarry be scarry...

[frank]

There's been a movie like this before in this section. Student Bodies? I think it was a more like comedy, remember something about a body count on screen...

[Javakoala]

Sounds an awful lot like "National Lampoon's Class Reunion"

http://www.imdb.com/title/tt0084395/

[Monster Jungle X-Ray]

I agree with Javakoala, haven't seen this in a long time, but it most definitely fits the description.