Have a go at stand-up paddle-boarding at Sidmouth.
Take a surf lesson together on the North Devon coast.
Hire a canoe or rowing boat or float along that canal on a horse-drawn barge.
Go river swimming at Culmstock or in the River Dart.
"A great experience, it had all the fun of camping, but with the added comforts of a proper bed, and a wood burning stove, plus the yurt was so cosy and beautifully decorated. The quiet rural surroundings made this a perfect place to get away from the busyness of everyday life and enjoy the scenery and peace - the only sounds were farm animals and bird song!"