The candidates attempt to walk across water with their DIY flotation footwear. It’s not as easy as it looks! Something like small canoes or giant water wings attached to your feet might work.
They would need to displace a weight of water equal to the weight of you plus the shoes. The challenge would be to make them easy to both balance and move in.
The shoes is part of it, but if you don’t have the legs then you’re not goin anywhere.Some students tried to keep their balance as the shoes wobbled on the surface of the water.
In my advanced physics class we had to build these shoes that allowed us to walk across the OLCHS pool. It was a great experiment and was a lot of fun.