Built in 1926, the school was named for Walter Scott Parker, who served on the School Committee (with some interruptions) for over 46 years. He was also on the Board of Library Trustees and was a state legislator and principal at the Bennett School in Boston for many years. The school is a member of the National Turning Points Network, a NELMS Spotlight Award Winning School and a Blue Ribbon Schools of Excellence Lighthouse School.

Its mission statement is: "At the Parker Middle School we strive to maintain a school culture that balances a rigorous and engaging learning community with a child-centered environment that honors the individual talents and struggles of every child. We acknowledge that, in the middle school years, our students face some of the most dramatic physical, social and emotional growth of their lives. Thus, it is our responsibility, in partnership with parents, to teach critical skills and provide the adult guidance that will help students grow to lead confident, responsible and productive lives."

There are 47.5 teachers who are all licensed in their teaching assignment. There are 187 classes in core academic areas.

The school's principal is Doug Lyons.