Today's science co-op had the kids building machines that would sort out marbles into three different cups based on size. There were some great ideas among the different groups...platforms with different sized holes cut in the bottom, a sort of maze where the kids manipulated the marbles with Popsicle sticks,and our teams tower - three Styrofoam cups with Popsicle sticks punched through the sides to trap the different sizes.
All in all it was a fun experiment, but a little frustrating for some of the kids. Best advice for doing this at home - enjoy making the machines, but don't turn it into a race. The kids had the most fun in the building and only became frustrated when it was turned into a competition.