One of the best party games for kids is the memory tray game - so why not turn it into a Halloween party game. All you need to do is find a load of scary objects - these could be plastic spiders, bats, skulls, etc. the sort of things you can buy cheaply in a dollar store. Around 20 items is ideal.
Put them on a tray and then cover them with a cloth. Give every child a peice of paper and a pen and then give them a minute to view the objects. Cover the objects up and then give them 2 minutes to write down all the items they remember. The child with the most correct answers is the winner.
Or we enjoy playing in teams best!