Play set:Reed's Gigantic Circus and Mammoth Hippodrome

Open-ended play, without predefined rules or strategies, allows children to create and explore new worlds and storylines. Play sets encourage this sort of unrestricted play, providing a child with a general context, a pirate ship or a country village, for instance, and leaving the rest up to the child's imagination. Early play sets, produced by companies such as McLoughlin Brothers and Milton Bradley in the late 19th and early 20th centuries, typically consisted of simple, easily assembled die cut wooden or cardboard pieces covered with bright, chromolithographed paper. Throughout the twentieth century manufacturing processes and materials evolved and play sets became more intricate, with pieces made of three-dimensional molded plastic. The basic concept, however, has remained the same. Whether simple or complex, made of wood or plastic, all play sets come to life with the addition of one key ingredient: a kid's imagination.