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 (2026)
- 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
Upcoming Events and News
- Tour - Mon., February 09, 2026 - get more information!
- Tour - Mon., February 23, 2026 - get more information!
- Open House - Sat., March 28, 2026 - get more information!
- Open House - Mon., April 06, 2026 - get more information!
- Open House - Mon., April 20, 2026 - get more information!
- Empty Bowls Event Nourishes Community Spirit and Action - 01/21/2026Principia 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 - 01/07/2026In 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 - 12/26/2025Principia 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 - 11/07/2025Principia 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 - 11/05/2025Principia'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.
- St. Louis Character: Teen DJ turns passion into nonprofit, teaching music and entrepreneurship - 10/25/2025A St. Louis teenager's journey from basement DJ to nonprofit founder is inspiring the next generation of musicians and entrepreneurs in unexpected ways
- Principia Is Helping Students Grow With Purpose - 10/16/2025Principia 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
- 4-star SG Quentin Coleman Commits to Wake Forest | No. 11 Overall SG - 10/14/2025Quentin Coleman, a top-ranked shooting guard, announces his college choice live. The skilled player, known for deep range and on-ball creativity, discusses the journey to this pivotal moment. This broadcast ...morefeatures highlights and an in-depth look at this rising star's decision. hide
- Principia School Ranked #1 Christian High School In St Louis and Missouri - 10/01/2025Principia School has once again been nationally recognized as one of the Best Schools in Missouri by Niche, the country's leading college and school search platform. Niche has ranked Principia ...moreSchool as the No. 1 Best Christian High Schools in Missouri and St. Louis, and No. 1 Best Christian K-12 Schools in Missouri and St. Louis. Principia also ranked as No. 2 Best Boarding High Schools in Missouri and St. Louis, and No. 4 Best Private K-12 Schools in St. Louis. hide
- ...read more
Top Rankings
Principia School ranks among the top 20 boarding schools (out of 275 schools) for:
Category
Attribute
School Resources
School Resources
Offering Breadth
School Overview
School Focus
College Preparatory
College Preparatory
Grades Offered (Boarding)
8-12
9-12
Grades Offered (Day)
PK-12
8-12
School Type
Co-ed
Co-ed
Year Founded
1898
1907
Campus Size
360 acres
130 acres
First Day of School
Wed. Aug 12, 2026
Last Day of School
Thu. May 27, 2027
Student Body
Enrollment
511 students
320 students
% Students of Color
31%
27%
% International Students
17%
21%
% Students Boarding
28%
66%
Offers Post-Grad Year
No
No
Academics and Faculty
Saturday Classes
Yes
No
Frequency of Saturday Classes
Weekly
Weekly
Student-Teacher Ratio
8:1
7:1
# of AP / Advanced Courses Offered
26
18
% Faculty with Advanced Degree
65%
73%
Summer Program Offered
No
Yes
Tuition Cost
Endowment Size
$590 million
$30 million
Yearly Tuition
(Boarding Students)
(Boarding Students)
$46,530
$69,500
Yearly Tuition
(Day Students)
(Day Students)
$25,010
$38,000
Tuition international students
$46,530
$58,300
% Students on Financial Aid
53%
40%
Avg. Financial Aid Grant
$17,000
$25,000
Admissions
Application Deadline
Jan. 13 / rolling
Jan. 15
SSAT Required
Yes
Yes
Acceptance Rate
62%
64%
Director of Admissions
Ginger Roth
Associate Director of Admissions
Jordan Poznick
Application URL
Course Listings
List of Courses Offered
AP / Advanced Courses
# of AP / Advanced 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
Sports
# Interscholastic Sports Offered
15
16
Extracurriculars
Total Extracurricular Organizations
13
23
Extracurriculars
Club or Organization:
E-SportsMath Olympiad
Mediation TeamMock Trial
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
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.
- Principia School accreditations: TABS, ISACS, ISSL
- 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
- School Motto: Lead with Love
- School Mascot: Panther
Source: Verified school update
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 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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