The children are given coloured sheets of paper that they fold into small boats that they then race, two at a time, on an easily accessible stream over a pre-established distance. If a boat gets stuck during the race, the child can use a stick to free it, he or she can do this twice. The boat that arrives first wins.
Practical information for parents: choose thick paper (at least a 100 grams). Remember to take your boat with you. Be kind to nature, do not leave any litter.
Instructions for folding a paper boat can be found here.