Abstract: A building set includes a plurality of building components. The components may be configured so that one or more predefined structures may be constructed with a set of the components. For example, the set of components may be configured any number of predefined structures may be constructed, such as a table and chairs, a boat, a plane, and so on. The components may be made from a composition including polyolefin. The polyolefin may have a density in the range of about 1 pound per cubic foot (lb/ft3) to about 9 lb/ft3. As such, the components are compressible, resilient, and elastic. One or more of the components may include a first retaining element, and one or more of the components may include a second retaining element. The retaining elements are configured to engage together for securing or coupling the components together.