#1 Largest Private Schools in Costa Mesa, CA
Mariners Christian School
Christian school (nondenominational) · Grades K–8
720 students
Costa Mesa, CA
B+Overall grade720 students14 students per teacher
2026 lists
Largest Private Schools in Costa Mesa, CA
The private schools in Costa Mesa, CA with the most students. Top 10 of 10 schools.
#2 Largest Private Schools in Costa Mesa, CA
St. John the Baptist Catholic School
Diocesan school · Grades K–8
505 students
Costa Mesa, CA
A+Overall grade505 students17 students per teacher
#3 Largest Private Schools in Costa Mesa, CA
The Waldorf School of Orange County
Independent school · Grades Pre-K–12
283 students
Costa Mesa, CA
BOverall grade283 students11 students per teacher
#4 Largest Private Schools in Costa Mesa, CA
St. Joachim Elementary School
Parish school · Grades K–8
244 students
Costa Mesa, CA
AOverall grade244 students15 students per teacher
#5 Largest Private Schools in Costa Mesa, CA
Renascence School International
Independent school · Grades K–11
96 students
Costa Mesa, CA
AOverall grade96 students6 students per teacher
#6 Largest Private Schools in Costa Mesa, CA
Pacific Academy
Independent school · Grades Pre-K–6
78 students
Costa Mesa, CA
A-Overall grade78 students6 students per teacher
#7 Largest Private Schools in Costa Mesa, CA
Page Academy
Independent school · Grades K–8
42 students
Costa Mesa, CA
AOverall grade42 students5 students per teacher
#8 Largest Private Schools in Costa Mesa, CA
Montessori Christian School
Christian (nondenominational) · Montessori · Grades Pre-K–5
28 students
Costa Mesa, CA
B+Overall grade28 students8 students per teacher
#9 Largest Private Schools in Costa Mesa, CA
International Christian Montessori Academy
Christian (nondenominational) · Montessori · Grades K–5
28 students
Costa Mesa, CA
B+Overall grade28 students6 students per teacher
#10 Largest Private Schools in Costa Mesa, CA
Christian Montessori School-Costa Mesa
Christian (nondenominational) · Montessori · Grades Pre-K–5
23 students
Costa Mesa, CA
AOverall grade23 students6 students per teacher
From official public records, updated October 2026.