we've had two large cardboard tubes sitting around the house from some oilcloth i purchased a few months ago... they've gone from room to room, inside and outside... serving as tunnels, ramps, amplifiers... i started wondering what else we can do with them. leo was a little concerned at first, since he wasn't quite sure he wanted to cut it up. but once reassured we still had one left that wouldn't be cut, he was intrigued. we gathered some materials... (i think i went a little overboard with the saw... a utility knife worked just fine. better, even.) cut the long tube into smaller sections... and then cut those sections in half... then hot glued them onto a large piece of cardboard. we gathered random things we thought might roll... (i had a pretty good suspicion that one of the things in that bucket wouldn't roll, but leo just wanted to make sure...) climbed up onto the stepstool, and tried it out! in the end, the ping pong balls and the wooden balls worked out the best... some larger things needed to be pushed along... once leo added the tunnels, the ping pong balls were the only ones to make it through. a great activity for shape identification, predictions (will it or won't it roll?), gross motor (we eventually tried to throw the ping pong balls onto the ramps from a distance), and just some general fun!