My boys are very much outside boys. They like to run, play, climb and wrestle outside. However when we moved to Kansas, the temperature outside was reaching a high of over 100 degrees. There was no way I was letting them outside. So we invested in a pop-up tent. The one I bought (from Walmart, very disappointed in Toys R Us and Target for not carrying these products in stock) is Cars themed. I wanted just plain multicolored, but had no such luck. It does have two play areas though - the actual tent with two entrances, and a tube that attaches to one of the entrances to crawl through. We have decided it's best to separate the two so Gabe and Zander have their own play areas. As you can see, Zander is a fan of the tube you crawl through. Even though the weather has gotten much better (today was a high of 65 degrees), both boys still very much enjoy their tents.
To anyone that has stir crazy children, pop-up tents are worth their weight in gold!