Not only are little kids contained by the the slippery sides, but older kids are also contained as they test their strength clinging to the sides, or just calmly lying back to enjoy the sights and sounds of nature.
First purchase a polypropylene tarp, UV resistant thread and rope, some very strong sewing machine needles, several ratchet straps, steel loops and strong strapping to sew to the diameter of the tarp, as well as extra for loops. The tarp is made of the same material as a trampoline bed.
After you have gathered your supplies assess the size and shape of you net.
Once you have determined you size and shape of your net you need to figure out where the strap needs to be sewed onto to tarp. You do not want to weaken the integrity of the tarp by cutting it, and you want your shape to be strong. If my tarp would have been larger I would have folded the tarp, so the fabric was double then sewed it. I did not want to cut the tarp so I rolled the edges to get the shape I wanted then sewed on the strap.
Next, sew the strapping onto the net leaving gaps so you can thread rope through the strapping to hold up the net. Sew lots to reinforce the bond between net and strap. If you put holes in the tarp or use existing ones, then the tarp will tear. Using strapping with reinforced spaces for rope eliminates this problem.
Once you have finished sewing on the strap it is time to attach attach the net to the trees. Ratchet straps work really well. I threaded rope through steel rings where I wanted ratchet straps to connect to the net. Using steel rings reduces the friction on the rope between the hooks of the ratchet straps and the rope. I also used a high strength, UV resistent rope.
Last, I devised a way for the kids to get into this net by attaching a cargo net. A rope ladder, or boards as a ladder attached to a tree would also work. This Big Kids Playpen has been frozen, filled with snow, held teenagers and adults and still has not weakened. In the summer it has attracted cocoons of certain moths mesmerizing the kids. It has also been used as a fort, a place to read a book, and as a containment centre for little ones when two adult hands have been needed.