South Mountain School
🇺🇸 Official data · 2025Millburn, New Jersey 07041 · Millburn Township School District
#20 of 1,479 elementary schools in New Jersey
#73 of 50,301 nationally
About South Mountain School
South Mountain School is a public elementary located in Millburn, in the Millburn Township School District school district of New Jersey, United States. It caters for Grades PK–4. In 2025 it enrolled 278 students. Traditional public schools run by a school district; free to attend.
Its Success Index (US) is 95.4 out of 100, placing it in the top 5% of elementary schools in United States and 20th of 1,479 ranked elementary schools in New Jersey. Its strongest component is community advantage (fewer free/reduced-price lunch) (100th percentile), and its weakest is students per teacher (91th percentile).
Other published figures: enrollment 278.
There are 5 schools in Millburn; South Mountain School ranks 3rd of 5 scored schools there.
Success Index (US) breakdown
Each component is a percentile against elementary schools across United States.
- Math proficiency (30%)82%
- Reading proficiency (30%)82%
- Community advantage (fewer free/reduced-price lunch) (25%)2.9%
- Students per teacher (15%)9.9
The Success Index (US) summarises published data about a school community. It is not a measure of teaching quality. Read the methodology.
Published measures
All figures published for South Mountain School by the official sources.
- Enrollment
- 278
- Students enrolled in the latest NCES directory year.
- Free/reduced-price lunch
- 2.9%
- Share of students eligible for free or reduced-price lunch.
- Students per teacher
- 9.9
- Enrollment divided by FTE teachers; not class size.
- Reading proficiency
- 82%
- Share of tested students proficient or above (all students, all grades).
- Math proficiency
- 82%
- Share of tested students proficient or above (all students, all grades).
Free academic assessment
Is your child on grade level in reading and math?
Success Tutoring offers personalised English and math tutoring from Kindergarten to Grade 12. Start with a free online assessment and a clear plan for the year ahead.
- Personalised learning plan mapped to the Australian Curriculum
- English & Maths from Kindergarten to Year 12
- Flexible memberships, no lock-in contracts
- Centres across NSW, VIC, QLD, WA, SA and ACT
Schools near South Mountain School
Closest schools by straight-line distance, with their Success Index (US).
Washington School
Millburn · Public middle · Grades 5–5
363 students · 1000 m away
Wyoming School
Millburn · Public elementary · Grades K–4
346 students · 1.1 km away
Millburn Middle School
Millburn · Public middle · Grades 6–8
1,106 students · 1.3 km away
Millburn High School
Millburn · Public high · Grades 9–12
1,380 students · 1.5 km away
Jefferson Elementary
Union · Public middle · Grades 5–5
564 students · 1.6 km away
James Caldwell Elementary School
Springfield · Public elementary · Grades 3–5
276 students · 1.7 km away
Jonathan Dayton High School
Springfield · Public high · Grades 9–12
654 students · 2.0 km away
Union High School
Union · Public high · Grades 9–12
2,410 students · 2.1 km away
Maplewood Middle School
Maplewood · Public middle · Grades 6–8
762 students · 2.1 km away
Battle Hill Elementary
Union · Public elementary · Grades PK–4
414 students · 2.2 km away
Similar schools
Public elementary schools in New Jersey with a comparable Enrollment.
Sunnybrae Elementary School
Hamilton · Public elementary · Grades K–5
278 students
Bradley Gardens Primary School
Bridgewater · Public elementary · Grades PK–4
279 students
Alice Costello Elementary School
Brooklawn · Public elementary · Grades PK–8
277 students
Charles R Smith Early Chilhood Center
Palisades Park · Public elementary · Grades PK–K
277 students
Kennedy Elementary School
Succasunna · Public elementary · Grades K–4
277 students
Berkeley Elementary
Westwood · Public elementary · Grades K–5
277 students
Frequently asked questions
Is South Mountain School a good school?
South Mountain School has a Success Index (US) of 95.4 out of 100 (Top 5% of elementary schools in United States) and ranks #20 of 1,479 in New Jersey. The index summarises published data about the school community and, where available, attainment; it does not measure teaching quality, so visit the school and ask about support at your child's level.
Where does South Mountain School rank in New Jersey?
South Mountain School ranks #20 of 1,479 elementary schools in New Jersey and #73 of 50,301 nationally on the Success Index (US) (2025 data).
How many students attend South Mountain School?
South Mountain School had 278 students in 2025.
Is South Mountain School a elementary school or a high school?
South Mountain School is classified as a elementary covering Grades PK–4. It is a public school.
What other schools are near South Mountain School?
There are 10 schools within 15 km of South Mountain School; they are listed on this page with their Success Index (US) and distance, and can be compared side by side.