American Boys Preparatory Academy Photo - American Boys Prep student learning at his own pace.

Best Mountainside Private Schools (2026)

For the 2026 school year, there are 3 private schools serving 238 students in Mountainside, NJ (there are 2 public schools, serving 748 public students). 24% of all K-12 students in Mountainside, NJ are educated in private schools (compared to the NJ state average of 14%).
The average acceptance rate is 75%, which is lower than the New Jersey private school average acceptance rate of 78%.

Private Schools in Mountainside, NJ (2026)

School
Location
Quick Facts
American Boys Preparatory Academy
American Boys Preparatory Academy Photo - American Boys Prep student learning at his own pace.
All-boys | Alternative School
(1)
1020 Springfield Ave
Mountainside, NJ 07092
(908) 516-4231
Gr: 5-8 | 12 students Avg. class size: 5 students Sports: 1 | Extracurrculars: 7 Tuition & acceptance rate listed
Kohler Academy
Kohler Academy Photo
Special Education School
1137 Globe Ave
Mountainside, NJ 07092
(908) 518-0021
Gr: PK-12 | 35 students
Primrose School At Mountainside
Daycare / Preschool
1038 Springfield Ave
Mountainside, NJ 70922
(908) 228-5589
Gr: PK-K | 191 students

Overview

This Town (Mountainside)
This State (NJ)
# Schools
3 Schools

Student Body:

# Students
238 Students
217,836 Students
% Average Students of Color
25%
40%

Academics and Faculty:

# Teachers
10 Teachers
20,228 Teachers
Average Student-Teacher Ratio
24:1
11:1
% Average Faculty w/Advanced Degree
50%
54%
Average Class Size
5 students
14 students

Tuition and Acceptance Rate:

Average Yearly Tuition Cost
$5,400
$18,757
Average Acceptance Rate
75%
78%

Students by Ethnicity:

0.35
0.63
# American Indian Students
n/a
942 Students
% American Indian Students
n/a
1%
# Asian Students
1 Student
11,318 Students
% Asian Students
n/a
5%
# Hispanic Students
5 Students
15,575 Students
% Hispanic Students
2%
7%
# Black Students
4 Students
14,114 Students
% Black Students
2%
7%
# White Students
25 Students
116,434 Students
% White Students
11%
53%
# Hawaiian Students
11 Students
292 Students
% Hawaiian Students
5%
n/a
# Two or more races Students
n/a
n/a
% of Two or more races Students
n/a
n/a
# Others Students
180 Students
59,276 Students
% of Others Students
80%
27%
All Ethnic Groups

Extracurriculars and Sports:

Average Number of Extracurriculars
7 extracurriculars
12 extracurriculars
Average Number of Sports
1 sports
7 sports

Frequently Asked Questions

How many private schools are located in Mountainside, NJ?
3 private schools are located in Mountainside, NJ.
What percentage of students in Mountainside go to private school?
24% of all K-12 students in Mountainside are educated in private schools (compared to the NJ state average of 14%).

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