As someone that has thrown many a Halloween party, I know tons of fun games to play at Halloween:
Mummy Wrap Race: choose someone (preferably an adult or older kid) and teams race to wrap the person with a roll of toilet paper without breaking the tp.
Build-A-Monster: Have pieces of a monster in a bag/folder/envelope and teams have to race to tape the monster together the right way. They can be made from felt, laminated construction paper, posters, etc. You can get as basic as head, chest, legs and arms; or you can get more detailed with eyes, mouth, feet, horns, etc.
Gross Guess: Have boxes with holes cut out for children to stick their hands in. Inside the boxes you can have bowls of peeled grapes, spaghetti, jell-o, and so on. Depending on how many kids go through, you might want additional back-ups on hand. The boxes should be labeled with "Eyes of Newt", "Witch's Hair", and things like that. It's more of an activity rather than a game.
Pass the Pumpkin: Musical chairs with a pumpkin being passed around. Play Halloween music, of course
Musical Tombstones: If you don't want kids throwing pumpkins, heh.
Ghost Bingo: I think you get it.
Eyeball Relay/Toss: Spoons with ping-pong balls decorated like eyeballs.
Creepy Costume Race: Have Halloween costumes with which teams have to dress up an adult. Pirate costumes work well for this.
Hope that helps!! If you have any more questions about these games or more games, feel free to ask.
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