Boarding School Review - Established 2003
Oldfields School
Academy of the Holy Family
Chatham Hall

Smallest Average Class Size

The average class size across the 18 ranked all-girls boarding schools is 11 (2026-27).
Among all-girls boarding schools, the one with the smallest average class size is Oldfields School, with 5.

Quick Facts (26-27)

  • # All-Girls Schools Ranked: 18
  • Top 20 Range (Smallest Average Class Size): 5–16
  • All-Girls Schools Avg.: 11
  • National Avg.: 13

Quick Facts (26-27)

  • # All-Girls Schools Ranked: 18
  • Top 20 Range (Smallest Average Class Size): 5–16
  • All-Girls Schools Avg.: 11
  • National Avg.: 13

National Average Class Size (Trends)

Showing 2016–2025. View full 21-year historical data

Total Growth: +2.4% (+0.3 since 2016)

Year National avg YoY Change (#) YoY Change (%)
2025 12.7 ▲ +0.1 ▲ +0.8%
2024 12.6 — 0 — 0.0%
2023 12.6 ▲ +0.1 ▲ +0.8%
2022 12.5 ▼ -0.3 ▼ -2.3%
2021 12.8 ▲ +0.2 ▲ +1.6%
2020 12.6 ▼ -0.1 ▼ -0.8%
2019 12.7 ▲ +0.1 ▲ +0.8%
2018 12.6 ▲ +0.1 ▲ +0.8%
2017 12.5 ▲ +0.1 ▲ +0.8%
2016 12.4 — 0 — 0.0%
2015 12.4 — 0 — 0.0%
2014 12.4 — 0 — 0.0%
2013 12.4 ▲ +0.1 ▲ +0.8%
2012 12.3 — 0 — 0.0%
2011 12.3 ▲ +0.1 ▲ +0.8%
2010 12.2 — 0 — 0.0%
2009 12.2 ▼ -0.1 ▼ -0.8%
2008 12.3 ▲ +0.1 ▲ +0.8%
2007 12.2 ▲ +0.1 ▲ +0.8%
2006 12.1 ▲ +0.2 ▲ +1.7%
2005 11.9 — —

Schools counted: listing status from database copies near the year end in 2012–2014, 2019 and 2022–2025; estimated listing status in 2015–2018, 2020 and 2021; archive coverage in 2005–2011 (a lower bound of the schools listed). The downloads give the source date of each year.

Download Table: Download as CSV | Download as XML | Download as JSON

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Show school map — National (# Students range: 5–16, avg 11)
# Students Range: 5 16 Avg. # Students: 11

Smallest Average Class Size (2026-27)

Among All-Girls Schools (out of 18 schools)

Sorted by range (alphabetically within range)
Oldfields School Photo - Oldfields School`s Mission is to embrace each student`s authentic self, educate through collaboration, empower the individual voice, and inspire confidence and continual growth, leading to a life of purpose.
#1Oldfields School
Gr: 8-12, PG
All-girls
1500 Glencoe Road
Sparks Glencoe, MD 21152
(443) 662-1009
(13)
5# Students
View Profile
Academy of the Holy Family Photo - Ambassadors Club
#2(T2–T4)Academy of the Holy Family
Gr: 9-12
All-girls (Catholic)
54 W. Main Street Box 691
Baltic, CT 06330
(860) 822-6279
8# Students
View Profile
Chatham Hall Photo - Our students thrive in a dynamic environment designed specifically for their success.
#2(T2–T4)Chatham Hall
Gr: 9-12
All-girls (Episcopal)
800 Chatham Hall Circle
Chatham, VA 24531
(434) 432-5516
(5)
8# Students
View Profile
Linden Hall School for Girls Photo
#2(T2–T4)Linden Hall School for Girls
Gr: 6-12, PG
All-girls
212 E Main Street
Lititz, PA 17543
(717) 626-8512
8# Students
View Profile
Grier School Photo
#5Grier School
Gr: 7-12, PG | 5-12, PG (day)
All-girls
2522 Grier School Road
Birmingham, PA 16686
(814) 684-3000
(6)
9# Students
View Profile
St. Timothy's School Photo - Completed in 2012, Dixon Hall is our state-of-the-art academic building. The technology-rich facility features the Taft Lecture Hall, the Coleman World Languages and Cultures Center, and a Center for Learning and Teaching.
#6St. Timothy's School
Gr: 9-12, PG
All-girls (Episcopal)
8400 Greenspring Avenue
Stevenson, MD 21153
(410) 486-7401
(2)
10# Students
View Profile
Emma Willard School Photo
#7(T7–T8)Emma Willard School
Gr: 9-12, PG
All-girls
285 Pawling Avenue
Troy, NY 12180
(518) 833-1320
(9)
11# Students
View Profile
Miss Hall's School Photo
#7(T7–T8)Miss Hall's School
Gr: 9-12, PG
All-girls
492 Holmes Road
Pittsfield, MA 01201
(413) 499-1300
(6)
11# Students
View Profile
Buffalo Seminary Photo - Our oldest tradition may be forward thinking but we are anchored in many other traditions too. Roses and white dresses for commencement. Our Social & Academic Honor Code. Morning Meeting to start the day. ..
#9(T9–T14)Buffalo Seminary
Gr: 9-12, PG
All-girls
205 Bidwell Parkway
Buffalo, NY 14222
(716) 885-6780
12# Students
View Profile
Dana Hall School Photo
#9(T9–T14)Dana Hall School
Gr: 9-12 | 5-12 (day)
All-girls
45 Dana Road
Wellesley, MA 02482
(781) 489-1331
(6)
12# Students
View Profile
The Madeira School Photo - Madeira's 376-acre campus in McLean, Virginia, overlooks the Potomac River from a perch just 12 miles northwest of Washington, D.C.
#9(T9–T14)The Madeira School
Gr: 9-12, PG
All-girls
8328 Georgetown Pike
McLean, VA 22102
(703) 556-8273
(2)
12# Students
View Profile
Miss Porter's School Photo
#9(T9–T14)Miss Porter's School
Gr: 9-12
All-girls
60 Main Street
Farmington, CT 06032
(860) 409-3530
(6)
12# Students
View Profile
Santa Catalina School Photo - Come visit our beautiful campus in Monterey, California! Call the admission office at 831.655.9356 or email admission@santacatalina.org to schedule your visit.
#9(T9–T14)Santa Catalina School
Gr: 9-12
All-girls (Catholic)
1500 Mark Thomas Drive
Monterey, CA 93940
(831) 655-9356
(1)
12# Students
View Profile
Westover School Photo
#9(T9–T14)Westover School
Gr: 9-12, PG
All-girls
1237 Whittemore Rd.
Middlebury, CT 06762
(203) 577-4521
(12)
12# Students
View Profile
Foxcroft School Photo - Schoolhouse
#15Foxcroft School
Gr: 9-12, PG
All-girls
22407 Foxhound Lane
Middleburg, VA 20117
(540) 687-4340
(9)
13# Students
View Profile
Saint Mary's School Photo - At Saint Mary's School, girls take center stage. We know girls and we know the all-girl learning environment at Saint Mary's School inspires girls to step outside their comfort zone, engage their minds, amplify their voices, and discover who they are and who they want to become!
#16Saint Mary's School
Gr: 9-12
All-girls (Episcopal)
900 Hillsborough Street
Raleigh, NC 27603
(919) 424-4100
(1)
14# Students
View Profile
Garrison Forest School Photo - One of the entrances to Garrison Forest School.
#17Garrison Forest School
Gr: 8-12 | PK-12 (day)
All-girls
300 Garrison Forest Road
Owings Mills, MD 21117
(410) 559-3111
15# Students
View Profile
Branksome Hall Photo - Branksome Hall
#18Branksome Hall
Gr: 7-12 | PK-12 (day)
All-girls
10 Elm Avenue
Toronto, Canada m4w 1n4
(416) 920-9741
(19)
>15# Students
View Profile

Frequently Asked Questions

Which all-girls boarding schools have the smallest average class size?
The all-girls boarding schools with the smallest average class size are Oldfields School, Academy of the Holy Family and Chatham Hall.
How many all-girls boarding schools are ranked for the smallest average class size?
18 all-girls boarding schools are ranked for the smallest average class size.

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Keep in mind that small statistical differences in average class sizes between schools do not always indicate better student performance at one school or another.
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