We are big suckers for indoor play structures, but there's always some hesitation about introducing new stuff and the attendant storage challenges. That's why this air fort rocks. It's a simple temporary structure that provides a unique sensory experience with everyday household objects.
To make your own air fort you'll need a big sheet, packing tape and a fan. That's it. If you happen to own a play parachute that would probably work fabulously as well. Check out the post at Mom Trusted for taping techniques, how to get the biggest bubble and tips on getting in and out of the fort. Then when you're done playing you pull up the tape and put away the fan and sheet.
(Images: Mom Trusted)

Shaw's Original Fir...
I slept under a sheet fort for many summers- I would position the fan to my bed & pull the sheet up & under the pillow. The fan billowed the sheet up & kept me cool for sleeping. Delightful.
I did this as a kid all the time!! I didn't use tape, I think I tucked the sheet ends under chairs. I can't remember how I fastened the sheet around the box fan, but it was a weekly occurrence! I'm glad you are passing this on!