Now includes a new student guide for Polyhedron Molecular Models to help students gain a deeper understanding of molecular structures!* A New Set of the Best Quality and the Best for Undergraduates (1) Hybrid orbitals: sp3, sp2, and sp atoms are easily recognized. (2) P, S, Cl, and metal atoms are included. (3) The set has many carbon atoms: 28 sp3-C and 12 sp2-C atoms. So, it is possible to construct a variety of molecules as exemplified below. (4) Bond lengths are easily recognized by color. (5) Smooth conformational changes such as the cyclohexane ring-flip. (6) Formation of three-membered rings such as cyclopropane and epoxide. (7) Electronic orbital plates are useful for studying -molecular orbitals. For example, the Woodward-Hoffmann rule shown below can be demonstrated by using this set.