A few activities using a ball on flat water with no gates. These could be adapted to moving water. The activities were designed to be done in pairs, as they were dreamed up by myself and Chloe during lockdown, but could easily be adapted to groups of 3. We also played with an adaptation of having 2 balls going per pair at once, so less rest time.
Chase and Throw
Does what it says on the tin! One paddler throws the ball in a direction of their choice - the other paddler sprints after it. As soon as they have it they throw it, and the first paddler sprints after it. Continue ad infinitum
Repetition without Repetition? Varying distances to sprint, angle and direction of turn before sprinting, vary size of ball to enable problem solving as to how to approach and pick it up.
Chase and Turn
Variation of the above but once at the ball the paddler does a 360 turn round it before picking it up. Decide if the paddler is allowed to touch the ball when turning, and if not then forfeits should be agreed in advance.
Repetition without Repetition? As above, but you could vary the strokes the paddler is allowed to use on the turn (could they do it entirely on bow draws?).
Chase and Dip
As the previous 2 but now the paddler must turn and dip their stern under the boat, and then pick it up on the other side. Video is here
Repetition without Repetition? As above. Stroke variation on the turn will vary where the boat ends up in relation to the ball. Letting go of the paddle in relatively less stable positions can pose problems.
Roll and Chase
We haven't tried this one yet - we'll save it for the summer! One paddler rolls and whilst they're upside down the other throws the ball in any direction. The first paddler rolls up and has to get to the ball as quickly as possible.
Repetition without Repetition? Orientation after the roll, amount of turn before the chase.
EDIT: Points scoring system adapted to differentiate
I played a version of this with Chloe last Sunday, and we adapted it into a competition. We played with a plastic duck instead of a ball. We started off with the rules as follows: 1 point for throwing the duck (!) and then the other person dips their stern under it and catches it on the other side (2 points)
After a few rounds I adapted it so Chloe had a second attempt at the dip and grab, with the second attempt being worth 1 point.
After a couple more rounds I changed the points system again for Chloe - 3 points for first attempt, 2 if she missed the duck but immediately pulled it in with a bow draw. 1 point if she caught it on her second run at the duck or if she managed to pull it in on a bow draw.
With the amendments it made for quite a close game - first to 50 points.
Good ideas, nice thanks.