Abstract: As the third paper of a series on the content update of European and American classic mechanics textbooks for science majors, this manuscript analyzes the ideas, the contents, and the features of 6 modern textbooks of classical mechanics. These textbooks pay more attentions to qualitative and quantitative characteristics of the solutions of differential equations of motion, and pay more attentions to qualitative analysis and numerical solutions. Chaotic dynamics is introduced into all the textbooks. Some textbooks for the advanced mechanics course include geometric descriptions of Lagrange mechanics and Hamiltonian mechanics with necessary fundamentals of global differential geometry, and essential algebraic structures of classical mechanics. However the textbooks for the intermediate mechanics course do not deal with algebraic structures and geometric descriptions of classical mechanics.