|The Walnut Park School is locally significant under Criterion C for the area of ARCHITECTURE as an excellent example of the property subtype E (Open) - Plan Elementary School defined in the Multiple Property Documentation Form St. Louis, Missouri, Public Schools of William B. Ittner. It meets the general registration requirements as well as those specific to the property subtype. The Walnut Park School retains excell .ent physical integrity of both original materials and characteristic plan shape. The pressed brick walls and slate roof are in good condition and, together with the half-timbering in the gable ends and limited use of stone trim at the primary entrance, communicate the Tudor Revival or Jacobethan style Ittner regularly employed between 1900 and 1910. The Walnut Park School retains the distinctive E-shaped (Open Plan) that Ittner and the St. Louis School District considered the most versatile and successful elementary school design, as described in the historic context The Refining of the 'Open Plan ' in St. Louis Public Schools, 1902-1910 in the amended MPDF. The building retains its historic form, including massing, roof shape, and fenestration. Areas with one-sided corridors have windows opposing the classrooms, providing natural light and ventilation. The building retains the concrete frame along with the wide corridors and stairwells designed to improve fire safety. Although the windows were replaced, the replacement windows match the historic windows in configuration and material on the front and side elevations, and in configuration on the rear elevation. The only addition to the Walnut Park School is a small gymnasium constructed in the 1980s. This tall rectangular block attaches to the southwest end of the rear south wing. It meets the registration requirements regarding additions in that it does not obstruct the adjoining elevation and attaches in a minimal, unobtrusive manner. The Walnut Park School is a remarkably intact E-Pian school built in 1909 and reflects Ittner's dedication to refining the Open Plan as the best possible design for public elementary schools in St. Louis. The period of significance is 1909, the date of construction.