Middle States Association Commissions on Elementary and Secondary Schools (MSA-CESS) Member Schools

BoardingSchoolReview.com lists 20 boarding schools as Middle States Association Commissions on Elementary and Secondary Schools (MSA-CESS) members, serving 6,631 students. Learn more about the association at Middle States Association Commissions on Elementary and Secondary Schools (MSA-CESS).

Membership data comes from the schools themselves and from published association directories. See all school associations.

Léman Manhattan Preparatory School Photo

The International School of Minnesota (ISM) Photo - Front Entrance to ISM. Our school is part of a global network of schools (SABIS), with schools in 20 countries and a 130+ year history!

Grier School Photo

The Hill School Photo - All students are required to attend sit-down family-style meals together in the Dining Room for lunch, and boarding students attend seated dinners several nights a week. Faculty members and their families join the students in a relaxed, yet formal atmosphere, where they enjoy interaction with one another outside of the classroom.

Solebury School Photo - Solebury School's Math and Science (STEM) program offers students opportunities to pursue AP and Honors classes, as well as Engineering courses that will prepare them for college.

ISI Academy Olympic Valley (formerly Lake Tahoe Prep) Photo - Lake Tahoe is a premier world-renown resort destination year-round. The blue skies, clear water, dense forests, and deep snow make it a haven for for everyone - from outdoor enthusiasts to authors and explorers.

Saint James School Photo - Founded in 1842, Saint James School is a coeducational, Episcopal boarding and day school for students in grades 8-12 located in Hagerstown, Maryland.

EF Academy New York Photo - Our campus is located an hour outside of New York City in the peaceful suburban community of Thornwood, New York.

The Knox School Photo - One of four elite sports programs on campus, Knox Crew is a year-round competitive sport, with training on the water from our campus shoreline and in our indoor rowing facility.

A+ World Academy Photo - At A+ World Academy, even Sundays are open for tutoring!

West Nottingham Academy Photo - Picture yourself at West Nottingham Academy. See yourself at West Nottingham Academy.

St. Andrew's School, DE Photo - Our 2100 acre campus is located in Middletown, DE just a short drive from Philadelphia, Baltimore, and Washington, D.C.

Lawrenceville School Photo - Tsai Field House opened in 2024 as a Community Hub and includes dining, recreation, and athletics. Photo: Jeremy Bittermann

The Kiski School Photo - Kiski's outdoor classroom and project-based learning culture gives boys the opportunity to get out of traditional four-walled classrooms and experience the beautiful scenery that Western Pennsylvania autumn offers! With our dedicated STEAM and Makerspace areas, our students get to roll up their sleeves and enjoy hands-on learning!

The Hun School of Princeton Photo - Preparing students to thrive in a world of constant change.

George School Photo

The International School of Schaffhausen Photo - The International School of Schaffhausen is located in the north of Switzerland, in the idyllic town of Schaffhausen. ISSH offers both the IB Diploma Programme and a High School Diploma Programme, with a focus on STEM subjects.

Ross School Photo - Ross School offers both seven- and five-dayboarding options for students in Grades 612and postgraduates. The boarding programprovides students with a "home away fromhome" in luxurious single-family houses in East Hampton and Sag Harbor, hosting student groups under the guidance and care of Ross faculty and staff.

Linden Hall School for Girls Photo

Mercersburg Academy Photo

The International School of Minnesota (ISM) Photo - Front Entrance to ISM. Our school is part of a global network of schools (SABIS), with schools in 20 countries and a 130+ year history!

The Hill School Photo - All students are required to attend sit-down family-style meals together in the Dining Room for lunch, and boarding students attend seated dinners several nights a week. Faculty members and their families join the students in a relaxed, yet formal atmosphere, where they enjoy interaction with one another outside of the classroom.

Solebury School Photo - Solebury School's Math and Science (STEM) program offers students opportunities to pursue AP and Honors classes, as well as Engineering courses that will prepare them for college.

ISI Academy Olympic Valley (formerly Lake Tahoe Prep) Photo - Lake Tahoe is a premier world-renown resort destination year-round. The blue skies, clear water, dense forests, and deep snow make it a haven for for everyone - from outdoor enthusiasts to authors and explorers.

Saint James School Photo - Founded in 1842, Saint James School is a coeducational, Episcopal boarding and day school for students in grades 8-12 located in Hagerstown, Maryland.

EF Academy New York Photo - Our campus is located an hour outside of New York City in the peaceful suburban community of Thornwood, New York.

The Knox School Photo - One of four elite sports programs on campus, Knox Crew is a year-round competitive sport, with training on the water from our campus shoreline and in our indoor rowing facility.

A+ World Academy Photo - At A+ World Academy, even Sundays are open for tutoring!

West Nottingham Academy Photo - Picture yourself at West Nottingham Academy. See yourself at West Nottingham Academy.

St. Andrew's School, DE Photo - Our 2100 acre campus is located in Middletown, DE just a short drive from Philadelphia, Baltimore, and Washington, D.C.

Lawrenceville School Photo - Tsai Field House opened in 2024 as a Community Hub and includes dining, recreation, and athletics. Photo: Jeremy Bittermann

The Kiski School Photo - Kiski's outdoor classroom and project-based learning culture gives boys the opportunity to get out of traditional four-walled classrooms and experience the beautiful scenery that Western Pennsylvania autumn offers! With our dedicated STEAM and Makerspace areas, our students get to roll up their sleeves and enjoy hands-on learning!

The Hun School of Princeton Photo - Preparing students to thrive in a world of constant change.

The International School of Schaffhausen Photo - The International School of Schaffhausen is located in the north of Switzerland, in the idyllic town of Schaffhausen. ISSH offers both the IB Diploma Programme and a High School Diploma Programme, with a focus on STEM subjects.

Ross School Photo - Ross School offers both seven- and five-dayboarding options for students in Grades 612and postgraduates. The boarding programprovides students with a "home away fromhome" in luxurious single-family houses in East Hampton and Sag Harbor, hosting student groups under the guidance and care of Ross faculty and staff.

Middle States Association Commissions on Elementary and Secondary Schools (MSA-CESS) Member Schools (2026-27)

School

Location

Quick Facts

A+ World Academy

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(8)

International (on a Tall Ship)
Kristiansand, Norway 4610
3475677083

Gr: 11-12, PG | 72 students Student-teacher ratio: 7:1 Avg. class size: 12 students Tuition listed

EF Academy New York

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(2)

582 Columbus Ave
Thornwood, NY 10594
(914) 495-6056

Gr: 9-12 | 290 students Student-teacher ratio: 8:1 Avg. class size: 15 students Tuition listed

George School

(Society of Friends)

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(9)

1690 Newtown Langhorne Road
Newtown, PA 18940
(215) 579-6547

Gr: 9-12 | 540 students Student-teacher ratio: 7:1 Avg. class size: 14 students Tuition listed

Grier School

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(6)

2522 Grier School Road
Tyrone, PA 16686
(814) 684-3000

Gr: 7-12, PG | 5-12, PG (day) | 235 students Student-teacher ratio: 6:1 Avg. class size: 9 students Acceptance rate: 50% Tuition listed

The Hill School

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(8)

860 Beech Street
Pottstown, PA 19464
(610) 326-1000

Gr: 9-12, PG | 539 students Student-teacher ratio: 7:1 Avg. class size: 10 students Acceptance rate: 25% Tuition listed

The Hun School of Princeton

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(1)

176 Edgerstoune Road
Princeton, NJ 08540
(609) 921-7600

Gr: 9-12, PG | 6-12, PG (day) | 700 students Student-teacher ratio: 8:1 Avg. class size: 14 students Tuition listed

The International School of Minnesota (ISM)

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6385 Beach Rd
Eden Prairie, MN 55344
(952) 918-1800

Gr: 8-12 | PK-12 (day) | 320 students Student-teacher ratio: 10:1 Tuition listed

The International School of Schaffhausen

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Mühlentalstrasse 280
Schaffhausen, Switzerland 8200
41526241707

Gr: 9-12 | PK-12 (day) | 280 students Student-teacher ratio: 6:1 Avg. class size: 17 students Tuition listed

ISI Academy Olympic Valley (formerly Lake Tahoe Prep)

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255 Olympic Valley Road | P.O. Box 2180
Olympic Valley, CA 96146
(801) 336-0753

Gr: 9-12 | 5-12 (day) | 35 students Student-teacher ratio: 7:1 Avg. class size: 7 students Acceptance rate: 80% Tuition listed

The Kiski School

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1888 Brett Lane
Saltsburg, PA 15681
(724) 639-8035

Gr: 9-12, PG | 205 students Student-teacher ratio: 6:1 Avg. class size: 11 students Acceptance rate: 65% Tuition listed

The Knox School

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(3)

541 Long Beach Road
Saint James, Long Island, NY 11780
(631) 686-1600

Gr: 6-12, PG | 130 students Student-teacher ratio: 6:1 Avg. class size: 12 students Acceptance rate: 75% Tuition listed

Lawrenceville School

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(6)

2500 Main Street
Lawrenceville, NJ 08648
(609) 895-2030

Gr: 9-12, PG | 844 students Student-teacher ratio: 7:1 Avg. class size: 11 students Acceptance rate: 18% Tuition listed

Léman Manhattan Preparatory School

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1 Morris Street
New York, NY 10004
(212) 232-0266

Gr: 9-12 | PK-12 (day) | 700 students Student-teacher ratio: 6:1 Avg. class size: 18 students Tuition listed

Linden Hall School for Girls

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212 E Main Street
Lititz, PA 17543
(717) 626-8512

Gr: 6-12, PG | 90 students Student-teacher ratio: 5:1 Avg. class size: 8 students Acceptance rate: 80% Tuition listed

Mercersburg Academy

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(20)

100 Academy Drive
Mercersburg, PA 17236
(717) 328-6173

Gr: 9-12, PG | 442 students Student-teacher ratio: 4:1 Avg. class size: 12 students Acceptance rate: 29% Tuition listed

Ross School

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18 Goodfriend Drive
East Hampton, NY 11937
(631) 907-5400

Gr: 6-12, PG | PK-12, PG (day) | 314 students Student-teacher ratio: 7:1 Avg. class size: 16 students Acceptance rate: 60% Tuition listed

St. Andrew's School, DE

(Episcopal)

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(13)

350 Noxontown Road
Middletown, DE 19709
(302) 285-4231

Gr: 9-12 | 315 students Student-teacher ratio: 5:1 Avg. class size: 12 students Acceptance rate: 22% Tuition listed

Saint James School

(Episcopal)

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17641 College Road
Hagerstown, MD 21740
(301) 733-9330

Gr: 8-12 | 260 students Student-teacher ratio: 6:1 Avg. class size: 11 students Tuition listed

Solebury School

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(4)

6832 Phillips Mill Road
New Hope, PA 18938
(215) 862-5261

Gr: 9-12, PG | 255 students Student-teacher ratio: 6:1 Avg. class size: 11 students Tuition listed

West Nottingham Academy

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(10)

1079 Firetower Road
Colora, MD 21917
(410) 658-9224

Gr: 9-12, PG | 65 students Student-teacher ratio: 7:1 Avg. class size: 10 students Acceptance rate: 80% Tuition listed

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