The 24 color bag has the basic 16 primary and pastel and 8 more colors we call the "naturals" for use with trees and flowers, water and wave! Crayon Rocks are simply the best coloring tool for young children! They are vibrantly colored and make beautifully textured artwork similar to oil pastels. These all-natural soy wax crayons are made from USA grown soybeans and colored with non-toxic pigment powders. They are designed to strengthen the tripod grip muscles in young children, preparing fingers and hands for handwriting. The shape allows small fingers to apply color in large, wide strokes.