#1 Private Schools with the Smallest Classes in St. Charles County, MO
Andrews Academy
Independent school · Grades K–8
4.7 students per teacher
Lake Saint Louis, MO
B+Overall grade123 students5 students per teacher
2026 lists
Private Schools with the Smallest Classes in St. Charles County, MO
Private schools in St. Charles County, MO with the fewest students per teacher (not counting preschools and special education schools). Top 25 of 25 schools.
#2 Private Schools with the Smallest Classes in St. Charles County, MO
Lafayette Academy
Independent school · Grades K–12
6.3 students per teacher
Lake Saint Louis, MO
B+Overall grade77 students6 students per teacher
#3 Private Schools with the Smallest Classes in St. Charles County, MO
St. John Paul II Preparatory
Independent Catholic school · Grades Pre-K–12
7 students per teacher
Saint Charles, MO
B-Overall grade176 students7 students per teacher
#4 Private Schools with the Smallest Classes in St. Charles County, MO
All Saints School
Parish school · Grades Pre-K–8
7.1 students per teacher
Saint Peters, MO
A+Overall grade125 students7 students per teacher
#5 Private Schools with the Smallest Classes in St. Charles County, MO
Duchesne High School
Diocesan school · Grades 9–12
8.2 students per teacher
Saint Charles, MO
A+Overall grade225 students8 students per teacher
#6 Private Schools with the Smallest Classes in St. Charles County, MO
St. Joseph School-Josephville
Diocesan school · Grades Pre-K–8
9 students per teacher
Wentzville, MO
A-Overall grade79 students9 students per teacher
#7 Private Schools with the Smallest Classes in St. Charles County, MO
St. Cletus School
Parish school · Grades Pre-K–8
9.5 students per teacher
Saint Charles, MO
A+Overall grade176 students10 students per teacher
#8 Private Schools with the Smallest Classes in St. Charles County, MO
Academy of the Sacred Heart
Independent Catholic school · Grades Pre-K–8
9.9 students per teacher
Saint Charles, MO
A+Overall grade164 students10 students per teacher
#9 Private Schools with the Smallest Classes in St. Charles County, MO
First Baptist Christian Academy
Baptist school · Grades Pre-K–8
10.8 students per teacher
O'Fallon, MO
B+Overall grade163 students11 students per teacher
#10 Private Schools with the Smallest Classes in St. Charles County, MO
Christian School District
Christian school (nondenominational) · Grades Pre-K–12
11.5 students per teacher
O'Fallon, MO
B-Overall grade596 students12 students per teacher
#11 Private Schools with the Smallest Classes in St. Charles County, MO
Sts. Joachim & Ann School
Parish school · Grades Pre-K–8
11.9 students per teacher
Saint Charles, MO
BOverall grade155 students12 students per teacher
#12 Private Schools with the Smallest Classes in St. Charles County, MO
Immanuel Lutheran School
Lutheran (Missouri Synod) school · Grades Pre-K–8
12.8 students per teacher
Saint Charles, MO
B-Overall grade366 students13 students per teacher
#13 Private Schools with the Smallest Classes in St. Charles County, MO
Child of God Lutheran School
Lutheran (Missouri Synod) school · Grades Pre-K–8
12.9 students per teacher
Saint Peters, MO
BOverall grade139 students13 students per teacher
#14 Private Schools with the Smallest Classes in St. Charles County, MO
Christian School District
Christian school (nondenominational) · Grades Pre-K–12
13.4 students per teacher
O'Fallon, MO
B-Overall grade596 students13 students per teacher
#15 Private Schools with the Smallest Classes in St. Charles County, MO
Assumption Catholic School
Parish school · Grades Pre-K–8
13.7 students per teacher
O'Fallon, MO
B-Overall grade374 students14 students per teacher
#16 Private Schools with the Smallest Classes in St. Charles County, MO
Immanuel Lutheran School
Lutheran (Missouri Synod) school · Grades K–8
14.5 students per teacher
Wentzville, MO
B-Overall grade385 students15 students per teacher
#17 Private Schools with the Smallest Classes in St. Charles County, MO
Lutheran High School of St. Charles County
Lutheran (Missouri Synod) school · Grades 9–12
15.3 students per teacher
Saint Peters, MO
BOverall grade460 students15 students per teacher
#18 Private Schools with the Smallest Classes in St. Charles County, MO
St. Theodore School
Parish school · Grades Pre-K–8
15.5 students per teacher
Wentzville, MO
B-Overall grade260 students16 students per teacher
#19 Private Schools with the Smallest Classes in St. Charles County, MO
Seton Regional Catholic School
Parish school · Grades Pre-K–8
16.4 students per teacher
Saint Charles, MO
BOverall grade248 students16 students per teacher
#20 Private Schools with the Smallest Classes in St. Charles County, MO
St. Patrick School
Diocesan school · Grades Pre-K–8
16.5 students per teacher
Wentzville, MO
B-Overall grade436 students17 students per teacher
#21 Private Schools with the Smallest Classes in St. Charles County, MO
St. Dominic High School
Diocesan school · Grades 9–12
16.7 students per teacher
O'Fallon, MO
B-Overall grade1,087 students17 students per teacher
#22 Private Schools with the Smallest Classes in St. Charles County, MO
Zion Lutheran School
Lutheran (Missouri Synod) school · Grades Pre-K–8
18.3 students per teacher
Saint Charles, MO
B-Overall grade364 students18 students per teacher
#23 Private Schools with the Smallest Classes in St. Charles County, MO
St. Paul Elementary School
Parish school · Grades Pre-K–8
19.1 students per teacher
Saint Paul, MO
B-Overall grade222 students19 students per teacher
#24 Private Schools with the Smallest Classes in St. Charles County, MO
Immaculate Conception School
Parish school · Grades Pre-K–8
19.2 students per teacher
Dardenne Prairie, MO
B-Overall grade715 students19 students per teacher
From official public records, updated October 2026.