The guide spoke about how the three main things you need if you were lost in the woods are food, water, and shelter. There's a lake off to the right a bit in this photo, providing the food and water for the hypothetical 'lost' circumstances. The kids were broken up into teams of three and sent out to build a shelter. Not just any shelter though, oh no. It had to fit all the team members, and be waterproof.
Little did they know the guide had plans to test the water proof-ness (after having them demonstrate how they could all fit inside) by splashing their structure with all available water bottles.
In the words of one of the Dads: The lesson we learned here is that we should never get lost in the woods with our kids.