Next to our sand area we have a water fountain with a faucet attached to it. We never really did much with it, and then this year I bought us a simple faucet.
I originally bought it thinking that they could use it to fill up buckets (which they still do, albeit slowly). However, its main use is to help kids rinse off the sand from their feet or hands.
Super useful!
Note: I originally called it a “feet washing station” but I wanted to avoid the misnomer as the kids were only rinsing off their feet, and not using soap.