Calm down GIZZYKINS
Suggestions for training games is an old favourite, "spitfires and Messershmits."
Basically fast circling of another yacht till someone stops . A great way to learn to keep a yacht moving.
If the kids can learn to tack effciently and then learn to accelerate downwind. they will become top sailors. The type of rig you are using is ideal for both things.
Having said all that, learn from MY mistakes

and wear helmet AND Seatbelt. and wear it tigh

Idea for a competition. Variations on the name GIZMO

but only if he doesnt mind and wont take offense.
Please GIZBIZ can we,can we,huh,huh,pleaseeeee