#1 Best Private Middle Schools in Boulder County, CO
Sacred Heart of Jesus School
Parish school · Grades Pre-K–8
The only Catholic school in Boulder
Boulder, CO
A+Overall grade169 students6 students per teacher
2026 lists
Best Private Middle Schools in Boulder County, CO
Private schools in Boulder County, CO with middle-school grades and the highest overall grades. Top 10 of 10 schools.
#2 Best Private Middle Schools in Boulder County, CO
St. John the Baptist Catholic School
Diocesan school · Grades Pre-K–8
The only Catholic school in Longmont
Longmont, CO
A+Overall grade185 students10 students per teacher
#3 Best Private Middle Schools in Boulder County, CO
St. Louis Catholic School
Parish school · Grades Pre-K–8
The only Catholic school in Louisville
Louisville, CO
A+Overall grade93 students8 students per teacher
#4 Best Private Middle Schools in Boulder County, CO
Shining Mtn. Waldorf High School
Independent school · Grades Pre-K–12
100% of graduates go to four-year colleges
Boulder, CO
AOverall grade188 students5 students per teacher
#5 Best Private Middle Schools in Boulder County, CO
Rocky Mountain Christian Academy
Christian school (nondenominational) · Grades Pre-K–8
Smaller classes than 73% of Christian schools in Colorado
Niwot, CO
A-Overall grade98 students7 students per teacher
#6 Best Private Middle Schools in Boulder County, CO
Boulder Valley Waldorf School
Independent school · Grades Pre-K–8
Smaller classes than 68% of independent schools in Colorado
Niwot, CO
A-Overall grade95 students5 students per teacher
#7 Best Private Middle Schools in Boulder County, CO
Boulder Country Day School
Independent school · Grades Pre-K–8
The largest independent school in Boulder
Boulder, CO
B+Overall grade281 students6 students per teacher
#8 Best Private Middle Schools in Boulder County, CO
Watershed School
Independent school · Grades 6–12
100% of graduates go to four-year colleges
Boulder, CO
BOverall grade114 students7 students per teacher
#9 Best Private Middle Schools in Boulder County, CO
Shining Mountain Waldorf School
Independent school · Grades Pre-K–12
One school from pre-K through 12th grade
Boulder, CO
B-Overall grade170 students10 students per teacher
#10 Best Private Middle Schools in Boulder County, CO
Friends School
Independent school · Grades Pre-K–8
One of 8 independent schools in Boulder
Boulder, CO
B-Overall grade134 students
Grades compare each school's official facts, such as class size, how long it has served families and where graduates go, with similar schools. They're a starting point: visit, ask questions and trust what you see.