Periodic Table Placemat by M. Ruskin Company helps a kids to master in new subjects. It is brightly colored and laminated. It comes with Rectangular shape. From pre schoolers to grandparents there is a placemat for everyone. This Periodic Table Covers chemistry essentials like: How to find the Mass Number; What happens when you remove a Proton from an Atom; What is the Atomic Number etc. On the back of each placemat, learning exercises based on the front are given.