I'm afraid my Halloween party will be lame, help please :(?

So I'm throwing a Halloween party in a few weeks for a bunch of 8th graders. (About 20...) But my house is so boring, there will be nothing to do!! We'll have lots of decorations and spooky music in the background and I was planning on putting on a scary movie sometime. But, the party is 5 hours long and a lot of the people coming aren't close friends. I don't want the party to be a flop, so I need help! I need ideas for entertainment. I don't have a pool or a pool table or any gaming systems and I feel like board games are totally out of the question. Any ideas on something else I could do? Please? Thanks!