Chris begins by adding rubber bands across the nails on one board, and then finds he can connect two boards in this way. Notice how the shape of the rubber band changes as he moves the boards, and what he discovers when he tilts one of the boards. As you can see, Chris decides to continue adding boards: "You can't get it" he tells Mark repeatedly, apparently meaning that by attaching them, he is establishing ownership of them – a prominent theme among three-year-olds!
Yet concern with ownership doesn't stop Chris and Johann from sharing boards the next day. And their animals enjoy sharing them as well – Johann holds up a rubber band for Chris' bird to go under.
