South Mountain School

Located at 2 SOUTHERN SLOPE DRIVE, in MILLBURN, New Jersey, South Mountain School is a modestly sized elementary campus that enrolls 278 students (grades pre-K through 4), run under Millburn Township School District. By comparison, New Jersey's public schools average about 405 students each, so South Mountain School sits 31% below that benchmark.

Across the 8 schools in Millburn Township School District (4,538 students total), South Mountain School accounts for its share of the district's footprint.

In terms of who attends, South Mountain School reports that 55% of the student body identifies as Asian. The remainder consists of 26% White, 8% multiracial, 6% Hispanic, 5% Black. The wider county runs roughly 6% Asian, putting the school's mix noticeably more Asian than the area baseline.

Looking at school resources, The school employs 29 full-time-equivalent teachers, for a student-teacher ratio near 9.7:1. Statewide, the average ratio sits near 11.4:1, putting South Mountain School tighter than the state norm the norm. Roughly 3% of students at South Mountain School qualify for free or reduced-price lunch, a number frequently used as a low-income enrollment indicator. That share is lower than Essex County's rate of about 54%.

After controlling for student poverty, South Mountain School ranks in the top 10% of New Jersey public schools. The BeatsExpectations model, a per-state regression of composite proficiency on FRL share, predicts schools with this student profile to land around 64.6%; South Mountain School posts 85.4%, +20.8 points above that line.

Around the school, census data for Essex County shows the typical household earns roughly $80,789 per year, about 39% of the adult population holds a bachelor's degree or above, and census figures put the poverty rate at about 11%. In all, Essex County runs 249 public schools (combined enrollment of about 145,473 students), of which South Mountain School is one.

Nearest neighbor: Washington School, around 0.6 miles off. 8 of the 8 nearest public schools sit inside a five-mile radius. On composite proficiency, South Mountain School comes 1st of 9 in the immediate cluster, higher than the nearby-schools average of 59.5%.

South Mountain School operates from a bedroom-community location.

Looking at the recent track record. Looking back 7 years, enrollment at South Mountain School has fell 13%, going from 318 students in 2018 to 278 in 2025. Over the same period, the White share declined from 41% to 26%. Class-load math has pulled in: from 11.9:1 in 2018 to 9.7:1 in 2025.

Within the allk12 community for this school, the page collects discussion, questions, and updates around fundraisers, lost-and-found posts, and report-card season. Anyone with firsthand experience at this school can post or comment.