If it weren’t for the pint-size stature of its third, fourth, and fifth grade occupants—and the telltale sounds of recess—one would think the new classroom building at the Riverdale Country School in the Bronx, New York, was the custom headquarters of a startup. Like a startup, the new Upper Learning Building by the New York–based firm Architecture Research Office (ARO) was designed with an entrepreneurial spirit, each detail meant to incubate ideas and foster innovative teaching and learning, with spaces scaled to the comfort and optimum productivity of its inhabitants.

Located on the progressive private school’s lower-school River Campus, which is nestled between the Hudson River and the 28-acre public garden called Wave Hill, ARO’s new structure for Riverdale’s older elementary school students is a low-slung, two-story rectangular volume that hugs a hill on both its eastern and northern elevations. 

(The Hill Campus, to the northeast, accommodates the middle and high schools.) A skirt of vertical zinc panels drapes the building’s northern end and the second story. The first floor is clad in lightweight, ultra-high-performance blue concrete panels of varying textures. The muted colors are a nod to the river and the sky.

Floor-to-ceiling windows and glazed entrances in the west-facing ground floor classrooms allow students to catch glimpses of the river, while deeply set openings on the second floor maximize light and views. “We liked the idea of students hanging out in the windows,” says ARO principal Stephen Cassell, who led the project with principal Kim Yao. At Riverdale, the outdoors is an important part of the curriculum, so the architects created a patio and path beside a grassy slope to the east. Classrooms there have doors that lead directly outside as well. (The architects worked with Matthews Nielsen Landscape Architects.)

The 23,000-square-foot building replaces an impermeable 1967 structure in the same site, which was universally disliked. Originally built for high school students, it had enfilade classrooms and expressed “sixties teaching values,” says headmaster Dominic A. A. Randolph. More recently, the old building housed an unwieldy library and a mix of prekindergarten, fourth-, and fifth-graders. The lower school’s cafeteria was housed in a lowceilinged room in one of two mid-to-late 19th-century houses—originally part of the Wave Hill estate—that now flank the new building and contain offices and other programs. Even so, Randolph asked the architects to explore saving and adapting the existing building. In the end, “it still wouldn’t meet our baseline, with right-sized classrooms near each other,” says Cassell. So the existing structure was razed, and, to house the students in the interim, ARO collaborated with the Rockwell Group to create a playful temporary campus by customizing 13 trailers (RECORD, January 2016).

As part of its scope, ARO was asked to help Riverdale with its master plan and programming, and to spiff up spaces in other lower-school buildings. Like many school campuses, Riverdale is a hodgepodge of styles and eras. The new building is “low and respectful of the two houses,” says Yao, and shows deference to the surrounding landscape.

In contrast to its predecessor, the new Upper Learning Building is “like a learning organism that you wander around in,” says Cassell. He and Yao situated a multipurpose space at each end of the building—a glasswalled cafeteria to the south and a theater (still under construction at the time of publication) with retractable seating to the north—using them as a framework. The classrooms in between are connected by hallways that double as places for serendipitous moments of connection and teaching, with writable and tackable walls. A large multipurpose room on the second floor is also a work in progress.

Throughout the building, ARO kept materials unfussy and durable, adding pops of blue in keeping with the sky and river theme. The architects worked with graphic design firm Open to inject otherwise blank surfaces with layers of learning opportunities. Four skylights on the second floor are made into teachable moments with graphics about the sun’s movement, while other bold visuals, such as the names of cities and countries, and even directionals, are spelled out in blue decals on the concrete hallway floors.

Design is very much at the heart of Riverdale’s philosophy. Randolph has been a vocal proponent of “design thinking” in schools and has forged an ongoing partnership between Riverdale and the global design firm IDEO, resulting in a downloadable Design Thinking Toolkit for Educators. The tool kit helps teachers through a process of research, ideation, and experimentation to solve challenges in classrooms—much the way a designer might in creating a better pair of scissors or a chair. In many ways, the new Upper Learning Building is design thinking writ large. It is a building born of exploration, deep discussions with educators about their needs and desires, and a willingness to tweak on the fly. “I’ve always believed that human-centered design is important and feeling is essential,” says Randolph, “but this is the first time I’ve seen these ideas realized to such an extent.”