Like the treehouse, but if that sheathing is the fibreglas product I used for a cover over an atrium some years ago in San Francisco, I hope the wind doesn’t come up too vigorously.
I found pieces of it in the streets and gutters blocks away. It just doesn’t have a lot of strength, IMHO. I notice that there seems to be pickets on the interior of the structure, which will tend to keep the children from kicking the panels loose….
…that, and the occasional admonition of ‘backside warming’ ought to keep the panels in place… ;)