Pinwheel is an American children's television series and the first to air on Nickelodeon, as well as the first to appear on its Nick Jr. block. The show was aimed at preschoolers aged 3–5. It was created by Vivian Horner, an educator who spent her earlier career at the Children's Television Workshop, the company behind Sesame Street. The show was geared to the "short attention span of preschoolers," with each episode divided into short, self-contained segments including songs, skits, and animations.

The series is set in a boarding house called Pinwheel House, which is powered by a pinwheel on the roof. The house's residents are a mix of live-action humans and puppets. Most of the show's songs are set to music in the style of a wind-up music box.

Pinwheel premiered on December 1, 1977, on Channel C-3 of QUBE's local cable system in Columbus, Ohio. In April 1979, Channel C-3 expanded into a national television network, now called Nickelodeon. Pinwheel continued to air on the network until 1990. From 1988 to 1990, Pinwheel was aired exclusively during the then-new Nick Jr. block. It was gradually phased out in favor of another preschool series, Eureeka's Castle. The Los Angeles Times called Eureeka's Castle a successor series to Pinwheel.