These are some of the things we’ve done with children at the guild I’m a member of - fun and get children really interested in crafts. The hula hoop rug is greeat for a group as it can build up and everyone has a go - this is one of the things I’ve been chatting to the teachers about and thinking of taking into school this year to do with dd’s class. I’ve been involved in making a couple of these with thick yarn and with tshirt yarn (recycled tshirts). I’ve seen the hula hoop one done with plastic bags too as a message about recycling, etc - looked cool too.
Easy looms can be made with just a piece of card or a small box (shoe boxes are great as they are usually strong enough to last a while.