This is my recently completed, (or at least nearly so; I'm always thinking of something else too add) play area for the kids.
I wanted to get some more swings, so that everyone could swing at the same time, but apparently swings have gotten ridiculously expensive in the few years since I bought one for Anna. Then Dave had to get tires for his truck, and I had a Eureka! moment. A tire swing would be so much cheaper, and all the kids could ride on it together. I asked Dave to save one of the truck tires, but instead of saving one of his old tires, he asked if he could have one of the tires laying around the garage. The guy said, "Sure, as long as you don't bring it back!" He got the biggest one there. The kids have loved it, and our whole family can fit on it!
We added some logs and mulch this past week, and now it's really nice under there. I read Robinhood to Anna while sitting on the logs yesterday. Almost as good as sitting under the greenwood tree.
The next thing I want to add is a pulley going from the top of the deck, down to the ground. As long as they don't pulley each other up, I think they will have fun with it. Although they would probably have fun pulling each other up until somebody falls, hits their head on a rock, and gets knocked out. Ask me how I know. ;)