St. Mark's School
Episcopal school · Grades 9–12
Southborough, MA
25 Marlboro Rd, Southborough, MA 01772
Overall grade: A+
ChooseAPrivateSchool.com grade, from official facts compared with similar schools.
- AClass size
- A-College-going
- B+Years serving families
- A+Diversity
What stands out
- The only Christian school in Southborough
- Smaller classes than 83% of Christian schools nationwide
- 91% of graduates go to four-year colleges
- Serving families in Southborough since at least 2011
In Southborough, Massachusetts, St. Mark's School is a Episcopal private school for students from 9th grade through 12th grade. About 377 students attend, with roughly 4 students per teacher, smaller classes than 83% of Christian high schools nationwide. The school reports that about 91% of its graduates go on to four-year colleges. The school day runs about 7 hours, 188 days a year.
At a glance
- Grades
- Grades 9–12
- Students
- 377
- Teachers
- 91 (full-time equivalent)
- Students per teacher
- 4.1
- Boys and girls
- Coed · 184 girls, 193 boys
- Religious affiliation
- Episcopal
- School day
- About 7 hours
- School year
- 188 days
- Graduates going to 4-year colleges
- About 91% (the school's estimate for the class before the survey)
- Library
- Yes
Reviews
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How it compares
- Smaller classes than 83% of Christian high schools nationwide (4 students per teacher).
- Larger than 85% of Christian high schools nationwide.
- Compared with 348 Christian high schools nationwide.
Students by survey year
Total students reported in official records since 2011–12.
Students by grade
Student body
Member of
- National Association of Independent Schools
- The Association of Boarding Schools
Questions to ask on a tour
- What is tuition, and what does it include (books, fees, uniforms, trips)?
- Do you offer financial aid, sibling discounts or payment plans?
- Do you accept ESA, voucher or tax-credit scholarship funds?
- How big are classes in my child's grade?
- What support is there for students who need extra help or more challenge?
- Is the school accredited, and by whom?
- What do a typical day and a typical week look like?
- How does the school communicate with families?
Questions about St. Mark's School
What grades does St. Mark's School serve?
St. Mark's School serves grades 9–12.
How many students attend St. Mark's School?
About 377 students, with 4 students per teacher, according to official records.
How much is tuition at St. Mark's School?
Call the school to ask about tuition, financial aid and payment plans.
Official record · Updated October 2026 · Official search · Something wrong? Tell us
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