Play-Doh is a modeling compound used by young children for art and craft projects at home and in school. Composed of flour, water, salt, boric acid, and mineral oil, the product was first manufactured in Cincinnati, Ohio, U.S., as a wallpaper cleaner in the 1930s. The product was reworked and marketed to Cincinnati schools in the mid-1950s. Play-Doh was demonstrated at an educational convention in 1956 and prominent department stores opened retail accounts. Advertisements promoting Play-Doh on influential children's television shows in 1957 furthered the product's sales.

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