Specialists in teaching mathematics to younger children have complained in print about the lack of general books to supplement their ventures into the development of concepts formerly associated with high school studies. This seems to be the sort of book they have been asking for. In words and photographs, the laws of mechanics are introduced through the common play experiences of children. The ""push and pull"" of the title stands for force. The forms of force are demonstrated with balloons, with water and with the games that children play. It is an elementary discussion of gravity, friction, the pendulum and the fulcrum made vivid by the clear black and white photographs of children at play. The explanations are carried in a vocabulary which allows 4th and 5th graders to use the book alone, although the special nature of the subject will probably require teacher-motivated readers. Teachers using the book will find it full of active demonstration ideas.