Boarding School Review - Established 2003

Principia School

13201 Clayton Rd St. Louis MO 63131
Tel: (314) 514-3188
www.principiaschool.org
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Quick Facts (26-27)

  • Grades: (Boarding Students) 8-12
  • Grades: (Day Students) PK-12
  • Enrollment: 511 students
  • Yearly Tuition (Boarding Students): $46,530
  • Yearly Tuition (Day Students): $25,010
  • Acceptance rate: 62%
  • Average class size: 15 students
  • Application Deadline: Jan. 13 / rolling
  • Source: Verified school update
Principia School Photo #4 - Principia Students are given many travel opportunities to not only grow in character, but to become global citizens.
Principia School Photo #5 - Principia's boarding program offers both domestic and international students from grades 8 to 12 the opportunity to live on campus.
Principia School Photo #6 - The Boarding Program is yet another way to make friends from around the globe.
Principia School Photo #7 - Principia's cheer team not only cheers for football and basketball, they also attend national competitions.
Principia School Photo #8 - As part of the Saint Louis Metro League, Principia plays local private schools in the Saint Louis and surrounding areas. Most notably, the boy's basketball team won the State Championship in March of 2025, and is ranked as #2 in the nation by Sports Illustrated.
Principia School Photo #9 - Our robust Performing Arts Center houses our music, theater, and dance programs offering 20+ performing arts opportunities each year. 100% of students receive musical instruments from Principia School.
Principia School Photo #10 - STEM at Principia Upper School is buzzing with two state-of-the-art IDEA Labs that serve our K-12 students. Students of all ages engage in problem solving, exploration in computer science, mathematics, software engineering, digital art, and communication. These high-tech workshops allow students the freedom to imagine and create.
Principia School Photo #11 - Principia Baseball focuses on teamwork and precision with vigorous training and regular practices.
Principia School Photo #12 - Boys and Girls tennis at Principia focuses on perseverance and character and offers both varsity and JV teams.
Principia School Photo #13 - Our Media and Communications center features a fully equipped television and sound recording studio and a Mac lab. Here, you'll find young creatives producing our School news show (Panther News Network), recording music, or airing a podcast episode.
Principia School Photo #14 - Students can enjoy our 360 acre campus on their way to sports practices, hangouts with friends, or walking to their favorite coffee shop just down the path from campus.
Principia School Photo #15 - Spiritual growth is the foundation of our boarding program and students daily join together for Bible study. These opportunities give students the space to share challenges with their peers gain inspiration on how to overcome these obstacles.
Principia School Photo #16 - Boys and Girls Soccer at Principia offers both varsity and JV athletes the opportunity to compete in the Saint Louis Metro League.
Principia School Photo #17 - Our four houses on campus come together periodically throughout the year for friendly competition in pursuit of the House Cup!
Principia School Photo #18 - Our robust visual arts program gives students real opportunities to share their gifts with the community. Our ninth graders recently painted a mural in our community and partnered with the city of Town and Country to make it happen.
Principia School Photo #19 - Upper School students have the unique opportunities to share their gifts with the community. Performance opportunities are encouraged throughout the year for student groups.
Principia School Photo #20 - Principia offers a college planning program for students designed to guide them through the research and application process. 96% of our graduates attend a college/university post graduation.
Principia School Photo #21 - House Competitions are a chance for students to come together as a team and show their school spirit in friendly competition.
Principia School Photo #22 - School spirit runs long and deep, with a vast network of alumni to support our students and campus.
Principia School Photo #23 - At Principia, we see our students as having limitless potential to reach new heights in their educational journey.
Principia School Photo #24 - We believe every student has everything they need to excel in the classroom, on the sports field, up on stage, and out in the community.
Principia School Photo #25 - We focus on developing the whole person with an approach that inspires every individual to be their best.
Principia School Photo #26 - Principia's experiential learning stretches from on-campus gardens, chickens, and a beehive to care for, to travel across the globe.
Principia School Photo #27 - Students are at the center of all we do. Because we want students to not merely know but to understand.
Principia School Photo #28 - All students (grades 5-12) participate in educational or character trips (domestic and abroad).
Principia School Photo #29 - With more than 20 sports and interscholastic activities, our program provides a rich variety of athletic opportunities to all students.
Principia School Photo #30 - On-site gardens reinforce values of stewardship, instill a love for service, and promote sustainability on campus.
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About the School

  • Imagine a place where opportunity is everywhere, and students are seen as limitless.
  • At Principia, we believe every student has everything they need to excel in the classroom, on the sports field, up on stage, and out in the community. We simply help uncover their boundless potential.
  • Much more than a pre-K-12 college-prep day and boarding school in St. Louis, Principia is founded upon principles that see students as boundless and divinely whole.
  • Grounded in the teachings of Christian Science, a worldwide Christian denomination, Principia welcomes students from all faith backgrounds.
  • Here, students become critical and creative thinkers who can address challenges through effective problem-solving.
  • Our 360-acre campus also offers a unique educational experience with beautiful indoor and outdoor learning spaces as well as state-of-the-art athletic facilities and fields.
  • Adventure and discovery await. Find your purpose at Principia School.

Quick Facts (26-27)

  • Grades: (Boarding Students) 8-12
  • Grades: (Day Students) PK-12
  • Enrollment: 511 students
  • Yearly Tuition (Boarding Students): $46,530
  • Yearly Tuition (Day Students): $25,010
  • Acceptance rate: 62%
  • Average class size: 15 students
  • Application Deadline: Jan. 13 / rolling
  • Source: Verified school update

School News

  • Empty Bowls Event Nourishes Community Spirit and Action - 01/21/2026
    Principia School recently hosted its 4th annual Empty Bowls Community Dinner, marking another successful year of giving back to the community. In partnership with Urban Harvest STL, the event contributed ...moreover $2,500 to the international Empty Bowls Project, which directly assists residents in the greater St. Louis area. hide
  • Winning Through Resolution: Principia Hosts Statewide Mediation Tournament - 01/07/2026
    In the fall of 2021, Principia School became the first high school in the United States to host a formal mediation tournament-a distinction that set a new benchmark for student-led ...moreconflict resolution programs nationwide. Five years later, Principia continues its leadership in this space. hide
  • Principia School Boys Basketball Takes Third Place at National Tournament - 12/26/2025
    Principia School boys basketball finished strong at the prestigious City of Palms Classic Basketball Tournament in Fort Myers, Florida, solidifying their own ranking as a top team in the nation. ...more hide
  • Learn & Grow - Principia School - 11/07/2025
    Principia School in Town & Country is highlighting its departure from traditional rote learning in favor of project-based and integrated education that develops students intellectually, morally, spiritually, physically, and socially. ...moreIt emphasizes how the school's "whole-person" approach and hands-on experiences empower students to become confident learners and purposeful leaders. hide
  • The Magic Behind the Curtain: Students Bring “A Wrinkle in Time” to Life - 11/05/2025
    Principia's Upper School students have poured countless hours of creativity, commitment, collaboration, and yes, heart, into crafting a performance that promised to transport the audience across time and space.
  • Principia Is Helping Students Grow With Purpose - 10/16/2025
    Principia School's faith-based, project-rich approach encourages students to lead their own learning while developing purpose, character, and academic readiness. It shows how small classes, hands-on experiences, and a global mindset ...moreunite to cultivate confident graduates prepared for college and beyond. hide
  • ...read more

Top Rankings

Principia School ranks among the top 20 boarding schools (out of 269 schools) for:

Category
Attribute
School Resources
Large financial endowment
School Resources
Highest endowment/student
Offering Breadth
High # of AP/advanced courses offered

School Overview

2026 School Data
Principia School
Boarding School Avg.
School Focus
College Preparatory
College Preparatory
Grades Offered (Boarding)
8-12
8-12
Grades Offered (Day)
PK-12
PK-12
School Type
Co-ed
Co-ed
Religious Affiliation
Christian
Non-denominational
Year Founded
1898
1906
Campus Size
360 acres
125 acres
Last Day of School
Thu. May 27, 2027
School Motto
Lead with Love

Student Body

Enrollment
511 students
320 students
% Students of Color
31%
27%
% International Students
17%
21%
% Students Boarding
28%
65%
Average SAT Score
1100
(Out of 1600)
* National Avg. »View
Average ACT score
27
(Out of 36)
*National Avg. »View
Offers Post-Grad Year
No
No

Academic Profile

Saturday Classes
Yes
No
Frequency of Saturday Classes
Weekly
Weekly
Classroom Dress Code
Casual
Uniform Dress
Casual
Average Class Size
15 students
12
* National Avg. »18
Student-Teacher Ratio
8:1
7:1
ESL Courses Offered
Yes
Yes
% Faculty with Advanced Degree
65%
73%
Summer Program Offered
No
Yes
Accreditations
Independent Schools Association of the Central States (ISACS)
National Association of Independent Schools (NAIS)
The Association of Boarding Schools (TABS)
# of AP Courses Offered
26
18
Courses
Advanced Art DCAdvanced Ceramics DC
Calculus ABCalculus AB DC
Calculus BCCalculus BC DC
College Algebra DCCollege Chemistry DC
College Precalculus DCComputer Science A
Computer Science PrinciplesEnglish Language and Composition
English Language and Composition DCEnglish Literature and Composition
English Literature and Composition DCField and Natural History DC
Music TheoryPhysics
Physics 1 DCSpanish 4 DC
Spanish 5 DCSpanish Language
Statistics DCU.S. Government
U.S. Government DCU.S. History DC

Tuition & Financial Aid

Endowment Size
$590 million
$30 million
Yearly Tuition
(Boarding Students)
$46,530
$71,500
Yearly Tuition
(Day Students)
$25,010
$40,000
Tuition international students
$46,530
$58,650
% Students on Financial Aid
53%
40%
Avg. Financial Aid Grant
$17,000
$25,000
Merit Scholarships Offered
Yes
Weekly

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Admissions

Application Deadline
Jan. 13 / rolling
Jan. 15
Accepts Standardized Application (SAO and/or Gateway)
Yes
No
SSAT Required
Yes
Yes
Acceptance Rate
62%
64%
Director of Admissions
Ginger Roth
Associate Director of Admissions
Jordan Poznick
Application URL
Online Application

Sports

# Interscholastic Sports Offered
15
17
Sports
BaseballBasketball
CheeringCross Country
Cross Country RunningDance
DivingField Hockey
FootballSoccer
SwimmingTennis
TrackVolleyball
Wrestling
School Mascot
Panther

Extracurriculars

Total Extracurricular Organizations
13
23
Extracurriculars
Club or Organization:
E-SportsMath Olympiad
Mediation TeamMock Trial
Model United NationsNational Honor Society
Poetry Out LoudRho Kappa Honor Society
Rotary ClubSpeech and Debate
Sustainability ClubTri-M
World Language Club

College Matriculation

College Acceptance Rate
96%
Year: 2011 - 2025
10 Most Popular College Choices  (# Enrolled)
Principia College
449
Saint Louis University
14
University of Missouri - Columbia
9
Lindenwood University
8
Truman State University
8
Butler University
6
Missouri S&T
6
Maryville University
5
University of Missouri - St Louis
5
Drake & Elon
4
View Matriculation Data

School Notes

  • Principia School is an independent, co-educational college preparatory school offering innovative programs for preschoolgrade 12. Grounded in the teachings of Christian Science, a worldwide Christian denomination, Principia welcomes students from all faith backgrounds. Through an integrated curriculum defined by rigor and opportunity, students learn to adapt and thrive in a rapidly changing world. Our hands-on approach develops critical and creative thinkers who can address relevant, global challenges through effective problem-solving. Our 360-acre campus offers an immersive and unique educational experience with beautiful indoor and outdoor learning spaces as well as state-of-the-art athletic facilities and fields. Principia's supportive community and character curriculum enables students to discover how living the values that uplift can improve the world around them.
  • Sample of notable school alumni/alumnae:
    • Lewis Howes (US’01, C’05) - New York Times bestselling author of The School of Greatness
    • Aaron Goldsmith (US’02, C’06)) - Broadcaster for the Seattle Mariners
    • Robert Duvall (US’49, C’53) - Academy award winning actor
    • Darcy Penick (US’96) - President of Bergdorf-Goodman
    • Marika McCauley Sine (US’96) - Chief Sustainability Officer at Starbucks
    • Kip Keller (US’19) - Professional soccer player - United Soccer League
    • Candy Crowley (US’66) - American news anchor who was CNN's chief political correspondent, specializing in American national and state elections
Source: Verified school update
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Frequently Asked Questions

How much does Principia School cost?
Principia School's tuition is approximately $46,530 for boarding students and $25,010 for day students.
What schools are Principia School often compared to?
Principia School is often viewed alongside schools like Missouri Military Academy by visitors of our site.
What is the acceptance rate of Principia School?
The acceptance rate of Principia School is 62%, which is lower than the boarding school average of 64%.
Who are famous alumni from Principia School?
Principia School famous alumni include: Lewis Howes (US’01, C’05), Aaron Goldsmith (US’02, C’06)), Robert Duvall (US’49, C’53), Darcy Penick (US’96), Marika McCauley Sine (US’96), Kip Keller (US’19) and Candy Crowley (US’66).
What sports does Principia School offer?
Principia School offers 15 interscholastic sports: Baseball, Basketball, Cheering, Cross Country, Cross Country Running, Dance, Diving, Field Hockey, Football, Soccer, Swimming, Tennis, Track, Volleyball and Wrestling.
What is Principia School's ranking?
Principia School ranks among the top 20 boarding schools for Large financial endowment, Highest endowment/student and High # of AP/advanced courses offered.
When is the application deadline for Principia School?
The application deadline for Principia School is Jan. 13 / rolling (applications are due on Jan. 13 but additional applications are reviewed year-round as space permits ).
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Quick Facts (26-27)

  • Grades: (Boarding Students) 8-12
  • Grades: (Day Students) PK-12
  • Enrollment: 511 students
  • Yearly Tuition (Boarding Students): $46,530
  • Yearly Tuition (Day Students): $25,010
  • Acceptance rate: 62%
  • Average class size: 15 students
  • Application Deadline: Jan. 13 / rolling
  • Source: Verified school update
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