Little engineers will have hours of construction fun building 3-D bridges! Kit includes plans for a standard arch bridge or design your own. The wooden foundation provides a sturdy work surface for building your elevated structure and can be enhanced with blue and green colored sand to signify land and water. Building bricks are joined with mortar (a special cement that you mix yourself) and best of all the bricks are reusable! Simply soak them in warm water and youï¾’re ready to build again. Ages 6-12.Contents: Reusable Bricks and Tiles, Wooden Foundation, Cement Powder, Trowel, Mixing Bowl. Detailed Instructions.