The top reported proficiency rate is 79% in Math. The lowest is 70% in Social studies.
Original Research by School Decision on Wm Diamond Middle
Wm Diamond Middle School is one of two public middle schools in Lexington, a suburban town located a short distance from downtown Boston. The school serves grades six through eight and is part of the Lexington Public Schools district, which is widely known for its academic reputation. Diamond is a regular public school, not a charter or magnet, and it operates as a traditional grade-level middle school.
Academically, Diamond performs at a high level. On the state’s NextGen MCAS assessments, the school’s overall proficiency across math, English language arts, science, and social studies places it in the top quartile when compared with other districts in Middlesex County. A clear majority of students meet or exceed state standards in each tested subject, with math and ELA proficiency rates well above the county median. Science proficiency, tested in grade eight, is similarly strong, and social studies, also administered in eighth grade, shows solid results though slightly lower than the other subjects.
However, looking at year-over-year trends, there has been a gradual decline in proficiency over the past several years. In both ELA and math, the share of students scoring proficient or above was higher in the pre-pandemic period and has not fully returned to those earlier peaks. The most recent data shows a modest recovery in ELA from the prior year, while math edged down slightly. This pattern is common across many schools nationally, but a parent may want to ask the school about specific efforts to reverse the longer-term trend, especially if they are comparing Diamond with its own past performance.
The student body is diverse in racial and ethnic composition. Just under half of the roughly nine hundred students are Asian American, with White students making up the largest single group after that. Students who identify as two or more races, Hispanic, and Black each represent smaller shares. The school does not report the share of students eligible for free or reduced-price lunch, nor does it provide data on students with disabilities or English learners, so it is not possible to characterize the socioeconomic or special-education profile from the available information. A parent considering Diamond should ask the district for those numbers to get a fuller picture of student support resources.
Lexington itself is a historically significant town with a walkable downtown centered on the Battle Green, independent shops and restaurants, and a strong cultural district. Major employers include pharmaceutical and biotech firms such as Takeda, defense contractor BAE Systems, and healthcare provider CareOne, giving the community a mix of professional and corporate character. The town has a notably high Asian population and a substantial share of foreign-born residents, reflecting its draw for educated workers in the greater Boston area. Housing costs are among the highest in the state, with both home values and rents far exceeding national averages. A family moving to Lexington for the school system should expect a significant financial investment in housing.
Diamond’s setting is suburban, with its own campus separate from the downtown core. The district includes six elementary schools, two middle schools, and a single high school that has won national science competitions multiple times. That high school is the eventual destination for Diamond graduates. Because Diamond is a middle school only, there is no graduation rate to report, and the school does not offer advanced placement or other high-school-level coursework by design.
What is missing from the public data may matter to some families. There is no reported information on chronic absenteeism, disciplinary incidents, staffing ratios, or course access, such as advanced math tracks or electives. These are common areas of interest for middle school families, and a parent should seek them directly from the school or district.
Wm Diamond Middle School fits a family seeking a high-performing academic environment in an affluent, diverse suburb with strong community resources. The proficiency numbers are very strong relative to the county, even if they have softened from earlier peaks. The school serves a well-resourced community, and the broader Lexington system offers a clear path to a celebrated high school. Families who value cultural diversity, historic character, and proximity to Boston will find the town appealing. Those concerned about the lack of socioeconomic and special-education data, or who want to understand how the school supports students who are not yet meeting benchmarks, will need to ask further.
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