Prang Large Crayons ClassacpkMade from a unique soybean oil formulation that makes Prang crayons brighter, smoother with less flaking than ordinary wax crayons. AP certified non toxic. 400 crayons: 50 each of 8 colours. Did you know? Soy beans grow in small pods that hang from plants. When processed, soybeans release soy oil that is turned into wax. Soy wax is plentiful and a renewable resource. Soy wax decomposes much more quickly than paraffin wax.