#1 Largest Private Schools in Longmont, CO
St. John the Baptist Catholic School
Diocesan school · Grades Pre-K–8
185 students
Longmont, CO
A+Overall grade185 students10 students per teacher
2026 lists
Largest Private Schools in Longmont, CO
The private schools in Longmont, CO with the most students. Top 5 of 5 schools.
#2 Largest Private Schools in Longmont, CO
Hillside School
Special education school · Grades 1–9
75 students
Longmont, CO
B+Overall grade75 students6 students per teacher
#3 Largest Private Schools in Longmont, CO
Longmont Christian School
Christian school (nondenominational) · Grades Pre-K–8
47 students
Longmont, CO
A+Overall grade47 students4 students per teacher
#4 Largest Private Schools in Longmont, CO
Boulder Sudbury School
Religious school · Ungraded
37 students
Longmont, CO
37 students11 students per teacher
#5 Largest Private Schools in Longmont, CO
Crossroads School
Christian school (nondenominational) · Grades 7–12
30 students
Longmont, CO
AOverall grade30 students7 students per teacher
From official public records, updated October 2026.