Weeding is one of the best gardening activities for little children. The weeds take enough muscle to be interesting but not enough to be over-hard. It's lends itself to repitition and is never-ending. The children seem to be on a treasure hunt when they're weeding and when one is weeding the rest will invariably follow. It doesn't hurt that weeding demands the prehensile grasp.
This is a shot of our one cucumber plant. Flower before Fruit.