Creating rafts can be great fun. The challenge was to work in a team to build a raft using only natural sticks (no planed wood) and two lengths of string. It must be small enough to fit in the pond and strong enough to support the weight of an egg for a minimum of 10 seconds.
The children were given a set time for their build, then the rafts were tested. This testing stage allows an opportunity to see how other teams have approached the task and design tweaks can be made. They could then make changes and retest. Once all teams had created a successful raft the children were then given time too use any additional materials either to add to their original build or to experiment with other designs.