Principia School
13201 Clayton Rd, Saint Louis, MO 63131Open, per Google (checked Sep 20, 2026)
Key facts
- Tuition, 2026-27
- From $14,900
- Grades
- PreK-12
- Students (K-12)
- 423
- Students per teacher
- 7.7
- Affiliation
- Other religious
- From Saint Louis center
- 12.4 miles
Can you use MOScholars here?
Missouri publishes no school list
- About the list
- How the MOScholars list works
- Applying
- You apply through one of the state-approved Educational Assistance Organizations, not to the state directly.
Source: MOScholars official source.
What you would pay here
- Net cost
- MOScholars’s 2026-27 amount per student is not yet verified word for word, so it is not subtracted. See the school’s tuition page
School facts
- Teachers
- 60
- Student body
- Coeducational
- Boys and girls
- 48% boys, 52% girls
- Go on to a 4-year college
- 98%
- Setting
- Suburb
- Partner list
- Partner school of a state-certified educational assistance organization (Herzog Foundation); not a state list
- Partner list: the organization’s own list, as of August 4, 2026.
- School facts, kindergarten to grade 12: U.S. Department of Education, NCES Private School Survey 2023-24, read September 20, 2026.
Where this comes from. Something wrong? Tell us and we will fix it.
Students and school year
Enrollment over time
- 2019-20 to 2023-24
- 331 to 423, up 92 (28%)
- Path
- Dipped to 15 in 2021-22, then passed its earlier level
Students by grade, 2023-24 (pre-K is not in the K-12 count)
- Largest grade
- Grade 12 (63)
- Smallest grade
- Grade 2 (13)
- Across the grades
- Classes fill up toward the upper grades
- High school grades
- Average 51; lower grades 25
The school year
- Days in the school year
- 166
- Length of the school day
- 7 hours 15 minutes
- Hours of school a year
- about 1,200
- Kindergarten
- Full day, 5 days a week
- Classes, 2023-24
- In person
- Library or media center
- Yes
- Year, against Missouri
- 8 days shorter than the 174-day median of 463 schools we list
- School day, against Missouri
- 15 minutes longer than the median of 7 hours (466 schools we list)
How it compares
- Students per teacher
- 7.7 here; median 8.6 at 114 MO combined schools
- Size in St. Louis County
- Larger than 123 of 141 other schools we list
Student body, 2023-24
Shares of K-12 students by race and ethnicity, as NCES reports them.
- Grades, school year and student body: U.S. Department of Education, NCES Private School Survey 2023-24, read September 20, 2026.
- Earlier counts: NCES Private School Survey 2019-20 and 2021-22, read October 14, 2026.
- Comparisons: the private schools ChoiceFunded lists, as of this page’s last update.
Principia School tuition, and what MOScholars pays
- Grades K to 5, 2026-27
- $14,900
- Grades 6 to 8, 2026-27
- $19,850
- Grades 9 to 12, 2026-27
- $22,800
Tuition from Principia School's website, checked October 5, 2026.
MOScholars Tax-credit scholarship
- Award
- Up to $7,145 per student for 2026-27, more for some students
- How it varies
- The law sets each ceiling as a share of the state adequacy target, which the Missouri education department lists as $7,145 for 2026-27: up to 100% of it for most students, 125% for students eligible for free or reduced lunch, 160% for English learners and 175% for students with an IEP. Worked example (our arithmetic, not a figure the state publishes): 175% of $7,145 is about $12,503. These are ceilings: assistance organizations may award less, and the average award in 2025-26 was $6,831.
Figures read from each program’s official pages, October 7, 2026. Sources and how to apply
What would you pay at Principia School?
Use $0 or more.
Tuition and fees MOScholars pays You pay per year Spread over 10 months
- Tuition filled in: the lowest published price we list (grades K to 5, 2026-27).
- Change them for your child’s grade.
- Type in the MOScholars figure from your award letter.
- Ask the school
- Whether its published 2026-27 tuition is still current; whether it takes MOScholars; its application deadline. More questions to ask
Tuition at nearby private schools
| School | Published tuition | Year | Miles |
|---|---|---|---|
| St. Louis Priory School | $31,500 | 2026-27 | 0.9 |
| Whitfield School | $37,400 | 2026-27 | 1.6 |
| Westminster Christian Academy | $24,900 | 2026-27 | 1.6 |
Each figure was read on that school's own website. Ranges run from the lowest to the highest grade band.
Other private schools nearby
| School | Grades | Students | Miles |
|---|---|---|---|
| St. Louis Priory School | 7-12 | 299 | <1 |
| Promise Christian Academy | K-12 | 41 | 1 |
| Rossman School | Not in the federal survey | 1 | |
| Saul Mirowitz Jewish Community School | K-8 | 149 | 1 |
| Whitfield School | 6-12 | 407 | 2 |
| Harper School | PreK-1 | 3 | 2 |
| Westminster Christian Academy | 7-12 | 940 | 2 |
| Kirk Day School | Not in the federal survey | 2 | |
Private schools
Keep looking
No new MOScholars application dates are posted yet. How MOScholars works.
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