We have a 8'x16' rectangle trampoline that has been inset into the ground, and it has good padding around all of the springs and the frame. The problem with this setup is that on rectangle trampolines, there are holes in each of the four corners that are about 2.5 feet wide that don't have springs or the side cover, and little kids can fall into those holes. I haven't been able to find anything specifically made to cover the holes, but I would really like to do it, if it is possible.
Any ideas on what we could use that would be strong enough to hold a kid who accidentally steps/falls into the hole, and yet is also soft enough to not hurt them if that happens? It has to be somehow attachable to a trampoline frame also.