Do you know about a "conning" competition? This is pretty wild.
This involves a two person team. Basically the "helmsman" (the one with the transmitter) faces away from the pond and the "pilot" passes verbal instructions the the helmsman.
The starting and ending points (can be the same) are usually some sort of dock requiring docking at the.
In-between are a number of obstacles to go around. This involves loops, turns, narrow passages, etc.
Missing the mark can involve deduction of points (if points are used) or having to turn around and redo the turn, etc. I like the later especially if on a clock timer from start to finish.
Have the course on a big board (like a map) is very handy. Set it by the water for the navigation team to view (see photo).