What: A home-made marble chase, built by the kids, on the back of the front door, made from toilet roll tubes and cardboard boxes.
How: I collected a bunch of toilet roll tubes and set a couple of small boxes aside from the recycling pile. I taped one of the tubes to the back of the door with masking tape, and when the kids had gathered to see what their crazy mother was doing this time, I dropped a marble in the tube and let it roll out. Then I gnashed my teeth and rent my hair and bewailed at the insufficiency of it all and said it Needed To Be Bigger. The kids took over at that point. My main contribution was to insist that they did one tube at a time and then tested the chase with a marble, so they could decide if they needed to move the tube closer or tilt it more or what. Sometimes the testing had to be done several times “just to be sure”. Sometimes they’d have to change something further back down the line because the marble now had more speed when it got to that point. They worked out for themselves that they might need to cut the end of a tube a bit so that it would catch the marble better. Kid 3 and Kid 5 both did really well with this, though I did need to stick around – if I wasn’t paying them my direct attention they tended to wander off to find me instead.