How would you go about controlling the decent of a marble to as slowly as possible? This is often done with a cascade of tracks on a wall. We wanted to know if Thin0nauts would come up with other ways.
Their final designs were based on using fluids. One placed the marble on top of a cone of sand and allowed it to sink as the sand ran away. The other used a mixture of flour and water to create a Non Newtonian fluid into which the marble sank. The gauge tracked the descent of the marble and the teams timed the movement of the pointer.
The sand was the slowest. We lost the other marble in floury goo and couldn't pull it out!
The challenge was to design an electric powered product that would operate from a solar panel when the sun came out.
The teams investigated a number of mechanical things that might move around and eventually decided to make a 'round the pole' flying exhibit. The plane would take off when the sun shone and land when it went in. Great fun but we burned out loads of motors with our huge solar panel and never managed to get a plane to actually take off from standstill, though they often flew quite well.
Could a design technology curriumum ever be complete without 'Automata'! Here our teams design simple shapes which pop up and down using cams and cranks.