In 2004, it was projected that within ten years, Southwest Academy, Woodlawn Middle School, Catonsville Middle School, Old Court Middle School, Pikesville Middle School, Sudbrook Magnet Middle School, Deer Park Middle School, and Franklin Middle School would be over enrolled by 677 students. It was evident a new school was needed.

Windsor Mill Middle School, the first new Baltimore County Public Schools middle school in 22 years, broke ground on Thursday, September 2, 2004 and opened for students on August 28, 2006. A community forum was held on January 18, 2006 for community members to discuss the boundaries for this new school. It was formally dedicated on October 16, 2006, with school and county officials gathered for a ribbon cutting ceremony. The event featured remarks by Superintendent Dr. Joe A. Hairston and Baltimore County Executive James T. Smith, Jr.

The approximate 35.5 acre Windsor Mill Middle School recreation and middle school site was purchased in 1970-1975. The building is a comprehensive 116,000-square-foot middle school with a capacity of about 715 students in grades six through eight. The $30.4 million school features a variety of amenities among its 38 classrooms, including three computer/technology labs, four science labs, a television and radio studio, two art studios, vocal and instrumental music rooms, and dance studio. It will serve not only the community's middle school needs, but serve as a focal point to provide many needed recreational opportunities for the entire area.