This picture brought back a bunch of memories – memories about how cool box forts can be:
Box fort – scroll down 4 pictures
All you need is old boxes and a little tape and kids can play for hours.
This reminded me of a box fort experience we had several years ago. We had moved from a small apartment into a larger house and brought a lot of stuff out of storage. Unpacking all of it generated many empty boxes, which we started to put in an empty room. After the room collected 20 or so boxes, the kids decided they were giant building blocks:
Eventually we had 50 or so boxes in the room, and the kids could build some pretty cool stuff.
Where do you get the boxes? If you know someone who has moved recently, that is an obvious source. If your office gets a bunch of new computers or something like that, there is another source. You can buy them new at lots of places, including U-Haul and Lowes. There are also places that sell used boxes.
For further inspiration see:
The “modern” version is pop-up nylon tents and tubes from makers like Play-hut as shown below: