River Day School, a private kindergarten through sixth-grade school, has leased the 4,400-square-foot former Sonitrol building, at 1627 E. Trent, along with an adjacent vacant lot, and plans to move there this spring, says Colleen Curran, executive director of the nonprofit school.

The school, which opened last year, currently shares space with Ascend to the Heights Child Development Center day care, at 116 W. Indiana, on Spokane's North Side.

"We've been subleasing from the day care, and we wanted our own building," Curran says.

The school has an enrollment of 20 students, up from 10 students when it opened. River Day School will have room to handle 45 students in the building on Trent Avenue, she says.

River Day School currently employs three full-time teachers, specialists in art and physical education, and one front-office person. The school envisions hiring another full-time teacher as it grows into the Trent facility.

Tenant improvements to the building there are being scheduled prior to River Day School moving in, Curran says. Upgrades will include tearing out some dividing walls to make larger classrooms, remodeling a break room, and adding a kitchen area.

"It's going to have a nice outdoor play area," she adds.

Kearns Construction LLC, of Spokane, is the contractor on the tenant improvement project.

The school advocates a constructivist educational philosophy in which learning activities integrate multiple subjects, says Gayle Peterson, head of the school.

"The curriculum flows between subjects," Peterson says. "They've never been isolated."

The school plans to move into the building on Trent by June, she says.

Spokane-based commercial real estate brokers Matt Byrd and Jeff Ottmar, of Cornerstone Property Advisors, and Mark Lucas, of Kiemle & Hagood Co., negotiated the lease.