ea. vol: diags. index. (How the World Works Series). CIP. Little. Oct. 1985. PLB $11.95. Gr 3-6 In explaining how two common items are manufactured, these books provide mini-lessons in economics by showing how the use of each product provides a livelihood for all of the people involved in the stages of manufacture. The Scoop on Ice Cream tells how each ingredient (sugar, milk, vanilla, chocolate) is produced and made into a form usable by the ice-cream factory, and what happens to it at the factory. There is a chapter on rating the quality of ice cream and a chapter on making homemade ice cream. Sneakers Meet Your Feet tells about the first sneakers and describes the anatomy of a foot. The following chapters explain how cotton, nylon and leather are made and how they are assembled into sneakers. The final chapter discusses fit. In addition to the economics lessons of supply and demand, readers are told that manufacturers try to keep the costs low by manufacturing sneakers in the Orient, where labor costs are lower. The black-and-white drawings and diagrams in these books are effective in showing how machines work and in labeling component parts. Suitable for purchase by all libraries, but especially by schools in which there is a curriculum need for this type of material. Margaret M. Hagel, formerly at Ryan Upper School Library, Norfolk, Va.