Play-Doh is a children's modeling compound made of flour, water, salt, boric acid, and mineral oil. It was first made in Cincinnati, Ohio, U.S., as a wallpaper cleaner in the 1930s. Children began using it as a modeling compound. It was changed and marketed to schools in the middle 1950s. Play-Doh was used at an educational convention in 1956. Important department stores opened retail accounts. Advertisements on many children's television shows in 1957 brought more sales. Play-Doh has much spinoff merchandise such as The Fun Factory. In 2003, the Toy Industry Association named Play-Doh in its "Century of Toys List".