Predicting what 3-dimensional shape might be formed when a 2-dimensional pattern was cut out and folded along dotted lines. Exploring faces and vertices.They discovered that both the tetrahedron and the pyramid have four triangular faces but that the pyramid also has a square base as its fifth face. Making structures out of toothpicks and gumdrops.
Learning that triangles made structures more stable because they formed a truss, which is a skeleton-like structure composed of struts, some of which are in compression and some in tension, which are joined to form a series of triangles. We looked at pictures of bridges which had trusses, which connected what they were learning to real-life situations. They had a wonderful time being creative and their structures just kept on growing!