Campbell Montessori School opened in 1989 as the St. Charles Montessori Academy. The school was granted nonprofit status in 1995 and later added an elementary school. In 1997, the renamed Campbell Montessori School opened at its current location. The school is located in a quiet neighborhood with a playground and wooded trails on six-and-a-half acres.
St. Theodore is a Catholic elementary school on Highway P in Wentzville. It serves children in kindergarten through eighth grade.
Mary Institute & Country Day School (MICDS) was founded in 1859 as a nonprofit, independent preparatory school offering education to students from pre-Kindergarten through 12th grade.
MICDS consists of three programs based on age with the pre-K through fourth grade age group represented by the Ronald S. Beasley Lower School, grades five to eight represented by a single-gender Middle School and grades nine to 12 represented by the Upper School.
The Head of MICDS is Lisa Lyle, formerly of the Blake School in Minnesota. There are 1,202 students enrolled at MICDS.