Ruffing Montessori School, the second oldest Montessori school established in the United States, was begun in 1959 through the efforts of the Cleveland Montessori Association. The organization founded and operated Montessori preschool and elementary classes in rented locations throughout Cleveland.

In 1964, a donation of a classroom building and property on Fairmount Boulevard in Cleveland Heights enabled the east side school to have a permanent location. In 1977, the east and west side schools separated, each retaining the name Ruffing in honor of Mary and Jim Ruffing, who led the Cleveland Montessori Association in its efforts to introduce Montessori to Northeast Ohio. With a current enrollment of 326, Ruffing in Cleveland Heights operates from a large, new facility, built according to LEED principles.

• http://www.ruffingmontessori.net/
• WKYC article about the school's environmental policies
• Ohio Association of Independent Schools
• Cleveland Council of Independent Schools
• Independent Schools Association of the Central States
• Ruffing Montessori School Photovoltaic Plant
• Heights Observer Article: Ruffing Montessori Demonstrates Curriculum in a Green School