Slates, Slide Rules, and Software: Teaching Math in AmericaDevoted to "tools used to teach math across American history, from the 1800s to the present." Includes information on slates, blackboards, arithmetic cards, geometric models, numeral frames, textbooks, geometric models, arithmetical frames, slide rules, blackboard dividers and protractors, B.F. Skinner's teaching machine, Cuisenaire rods, the new math, calculators, software, and geoboards. From the Smithsonian National Museum of American History, Behring Center