Is it permissible to paddle a kayak or use a water tube with a seat, where one does not actually go into the water, during the 9 days?


Strictly speaking it is permitted, but is discouraged, as one should avoid activities which pose a danger during the nine days.

Effort should be made that only face, hands and feet become wet, or only a minor portion of the body.


See here:

I direct a Yeshivas Kayitz and The head counselor planned a trip of horseback riding for one of the nine days. Is this a problem? Also, Is it Okay, instead of swimming, to have the boys play in water sprinklers during the nine days?