My dad would like to organise some games for junior sailors at our club and I was wondering what games you found interesting on your sailing boat.

Normal racing won't cut it?

no I dont thing so

Do relay races with frisbee's...Do a lap, throw frisbee from 25 yards from the beach, your team catches it and goes. If the frisbee goes in the water you have to swim to get it, so a good throw will really earn you some time.

racing with lemans starts!! meaning you start on the beach and run to your boat and launch it. mixes things up

I played the pie melon game and it was awesome

Great games that are also excellent training include sailing backwards, sailing without rudders, blindfold the skipper (assuming there is a crew on the boat )
also
balloon chases
tag

sounds like fun Ill try all but the blindfold the skipper with my crew
Ill end up with a hole in my boat

Games on sailing boats are very dangerous for unexperienced sailor. But some junior
sailor are very intelligent and gained experience very early. They can enjoy the
games on any kind of sailing boats.