Serving 724 students in grades 9-12, Mark T. Sheehan High School ranks in the top 50% of all schools in Connecticut for overall test scores (math proficiency is top 50%, and reading proficiency is top 50%).
The percentage of students achieving proficiency in math is 40-44% (which is approximately equal to the Connecticut state average of 40%). The percentage of students achieving proficiency in reading/language arts is 60-64% (which is higher than the Connecticut state average of 50%).
The student:teacher ratio of 11:1 is lower than the Connecticut state level of 12:1.
Minority enrollment is 35% of the student body (majority Hispanic), which is lower than the Connecticut state average of 53% (majority Hispanic).
Quick Stats (2025)
- Grades: 9-12
- Enrollment: 724 students
- Student:Teacher Ratio: 11:1
- Minority Enrollment: 35%
- Graduation Rate: 95% (Top 50% in CT)
- Overall Testing Rank: Top 50%
- Math Proficiency: 40-44% (Top 50%)
- Reading Proficiency: 60-64% (Top 50%)
- Science Proficiency: 65-69% (Top 20%)
- Source: National Center for Education Statistics (NCES), CT Dept. of Education
Top Rankings
Mark T. Sheehan High School ranks among the top 20% of public schools in Connecticut for:
Category
Attribute
Most improved public schools
Science Proficiency
Student Attention
School Overview
Mark T. Sheehan High School's student population of 724 students has declined by 8% over five school years.
The teacher population of 63 teachers has declined by 10% over five school years.
Grades Offered
Grades 9-12
(offers virtual instruction)
(offers virtual instruction)
Total Students
724 students

Gender %

Total Classroom Teachers
63 teachers

Students by Grade

School Rankings
Mark T. Sheehan High School ranks within the top 50% of all 942 schools in Connecticut (based off of combined math and reading proficiency testing data).
The diversity score of Mark T. Sheehan High School is 0.53, which is less than the diversity score at state average of 0.68. The school's diversity has stayed relatively flat over five school years.
Overall Testing Rank
#397 out of 942 schools
(Top 50%)
(Top 50%)

Math Test Scores (% Proficient)
40-44%
40%

Reading/Language Arts Test Scores (% Proficient)
60-64%
50%

Science Test Scores (% Proficient)
65-69%
47%

Student : Teacher Ratio
11:1
12:1

American Indian
n/a
n/a
Asian
6%
5%

Hispanic
21%
31%

Black
3%
12%

White
65%
47%

Hawaiian
n/a
n/a
Two or more races
5%
5%

All Ethnic Groups



Graduation Rate
95%
89%

Eligible for Free Lunch
24%
37%

Eligible for Reduced Lunch
6%
6%

School Statewide Testing
School District Name
Source: National Center for Education Statistics (NCES), CT Dept. of Education
Profile last updated:
Frequently Asked Questions
What is Mark T. Sheehan High School's ranking?
Mark T. Sheehan High School is ranked #397 out of 942 schools, which ranks it among the top 50% of public schools in Connecticut.
What schools are Mark T. Sheehan High School often compared to?
Mark T. Sheehan High Schoolis often viewed alongside schools like Lyman Hall High School by visitors of our site.
What percent of students have achieved state testing proficiency in math and reading?
40-44% of students have achieved math proficiency (compared to the 40% CT state average), while 60-64% of students have achieved reading proficiency (compared to the 50% CT state average).
What is the graduation rate of Mark T. Sheehan High School?
The graduation rate of Mark T. Sheehan High School is 95%, which is higher than the Connecticut state average of 89%.
How many students attend Mark T. Sheehan High School?
724 students attend Mark T. Sheehan High School.
What is the racial composition of the student body?
65% of Mark T. Sheehan High School students are White, 21% of students are Hispanic, 6% of students are Asian, 5% of students are Two or more races, and 3% of students are Black.
What is the student:teacher ratio of Mark T. Sheehan High School?
Mark T. Sheehan High School has a student ration of 11:1, which is lower than the Connecticut state average of 12:1.
What grades does Mark T. Sheehan High School offer ?
Mark T. Sheehan High School offers enrollment in grades 9-12 (offers virtual instruction).
What school district is Mark T. Sheehan High School part of?
Mark T. Sheehan High School is part of Wallingford School District.
School Reviews
5 7/10/2008
very good teachersa nd art/music programs. Good for fostering student growth and community. Lots of sports and activities.clubs for everyone!
Review Mark T. Sheehan High School. Reviews should be a few sentences in length. Please include any comments on:
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