Lex and I used his 14-in-1 Solar Robotics Kit to construct a surfing robot. Think of a guy padding out on his surfboard on his way to catch the waves.
Then, we took it to our pool to test it out. Connor thought it would be safer to test it in our bathtub, and that might have been a good idea, except for the whole solar-powered thing. There are exactly zero windows in our two bathrooms.
It worked, but the waves in the pool were a little too large for our little bot, and it kept capsizing.