#1 Best Private High Schools in St. Charles County, MO
Duchesne High School
Diocesan school · Grades 9–12
Smaller classes than 83% of Catholic schools in Missouri
Saint Charles, MO
A+Overall grade225 students8 students per teacher
2026 lists
Best Private High Schools in St. Charles County, MO
Private high schools in St. Charles County, MO with the highest overall grades. Top 6 of 6 schools.
#2 Best Private High Schools in St. Charles County, MO
Lutheran High School of St. Charles County
Lutheran (Missouri Synod) school · Grades 9–12
89% of graduates go to four-year colleges
Saint Peters, MO
BOverall grade460 students15 students per teacher
#3 Best Private High Schools in St. Charles County, MO
St. John Paul II Preparatory
Independent Catholic school · Grades Pre-K–12
The smallest classes of any Catholic school in Saint Charles
Saint Charles, MO
B-Overall grade176 students7 students per teacher
#4 Best Private High Schools in St. Charles County, MO
St. Dominic High School
Diocesan school · Grades 9–12
The largest of 188 Catholic schools in Missouri
O'Fallon, MO
B-Overall grade1,087 students17 students per teacher
#5 Best Private High Schools in St. Charles County, MO
Christian School District
Christian school (nondenominational) · Grades Pre-K–12
The largest Christian school in O'Fallon
O'Fallon, MO
B-Overall grade596 students12 students per teacher
#6 Best Private High Schools in St. Charles County, MO
Christian School District
Christian school (nondenominational) · Grades Pre-K–12
The largest Christian school in O'Fallon
O'Fallon, MO
B-Overall grade596 students13 students per teacher
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.