I know you said no organized games, but their are tons of cheap relay type games they could do that would really require little effort on your part. We have done the wet t shirt relay where the kids each have a large tshirt on, starting in one spot have to run to the other side of the yard to a bucket of water, take the shirt off, soak it, put it back on, race back, take it off and wring it out in another bucket and see who can reach the designated line first. Another one is similar if the weather doesnt permit, where they have to carry pebbles in their toes across the yard and put them in a mason jar; whoever gets the most in a certain amount of time wins. Their are tons out there....google cheap party games. If not utilize what you have, do toy stations, where they move from one set up of toys to another after a certain amount of time, so theyre not getting bored. You could do the same type of circuit style play with cheap stuff from the dollar store, chalk, bubbles, even balloons. Theirs like a million and five things you can do with balloons. If theyre all girls, do mani/pedi, hair and makeup stations. again, dollar store stuff, kids love that junk. It doesnt take much to impress a little kid, trust me! Just get creative and keep em busy and theyll think they had the time of their lives. Check pinterest too, great ideas there....we had a cinco de mayo party that was pretty awesome yesterday, decorations, pinata and 2 different crafts, all for $15.90.