Dorothea Marie Lensch was born in 1907 in Portland, Oregon, the daughter of German immigrants. She studied at Mills College in Oakland, California, the University of Oregon in Eugene, and Wellesley College in Massachusetts. In the early 1930s, she taught at Rockford College in Rockford, Illinois, and at George Washington University in Washington, D.C.; she headed the dance department at both schools. In 1936, she returned to Portland, and in September of that year was named supervisor of playgrounds for the Bureau of Parks and Public Recreation, a position later known as director of recreation.

During her tenure, Lensch expanded the bureau's programs to include multiple sports and arts, as well as arts and crafts lessons, and helped establish the Ballet Workshop, the Junior Museum (later the Portland Children's Museum), the Art Center, and the Washington Park Music by Moonlight Festival. She also established recreational programs specifically for children with intellectual disabilities.

Lensch retired in 1972, and remained active. She died in 2000.

Sources: "Dorothea Marie Lensch (1907-2000)," by Devin Busby, Oregon Encyclopedia, https://www.oregonencyclopedia.org/articles/lensch-dorothea/; articles in the Oregonian, September 9, 1936 and July 29, 2000.