First, you place the car helter skelter in an elevated postition:
Then you pour a jar of beads down it:
And catch them with various vessels:
Then it gets more complicated. You add obstacles on the helter skelter such as blocks and cars, position catching vessels such as dumper trucks and diggers at different distances from the bottom of the helter skelter, and add slides and other paths for the beads to follow:
After every change you retorically ask with glee, "What's going to happen?!"
Yes, that was the best 99p I've spent recently!
We've threaded the beads on thread using needles, sorted them, "cooked" with them, rolled them down things to investigate the effects of slope and friction and made interesting patterns. Here are Nathaniel's flowers: