Here’s a great idea (it was Mr K’s).
Cut out a big piece of paper and get your child to lie on top of it while you trace around his/her body. Give him/her a bunch of crayons and this will keep them occupied for ages! It’s also great to do when they have friends come over to play and they want to do some crafts. (Gives you a bit of a break as they are busy colouring in) .