Serving 466 students in grades 9-12, Haddam-killingworth High School ranks in the top 30% of all schools in Connecticut for overall test scores (math proficiency is top 30%, and reading proficiency is top 30%).
The percentage of students achieving proficiency in math is 55-59% (which is higher than the Connecticut state average of 41%). The percentage of students achieving proficiency in reading/language arts is 70-74% (which is higher than the Connecticut state average of 50%).
The student-teacher ratio of 10:1 is lower than the Connecticut state level of 12:1.
Minority enrollment is 12% of the student body (majority Hispanic), which is lower than the Connecticut state average of 54% (majority Hispanic).
Quick Facts (2026)
- Grades: 9-12
- Enrollment: 466 students
- Student-Teacher Ratio: 10:1
- Minority Enrollment: 12%
- Graduation Rate: ≥95% (Top 10% in CT)
- Overall Testing Rank: Top 30%
- Math Proficiency: 55-59% (Top 30%)
- Reading Proficiency: 70-74% (Top 20%)
- Science Proficiency: 45-49% (Btm 50%)
- Source: National Center for Education Statistics (NCES), CT Dept. of Education
Top Rankings
Haddam-killingworth High School ranks among the top 20% of public schools in Connecticut for:
Category
Attribute
Reading/Language Arts Proficiency
Graduation Rate
Student Attention
School Overview
Haddam-killingworth High School's student population of 466 students has declined by 24% over five school years.
The teacher population of 49 teachers has declined by 9% over five school years.
Grades Offered
Grades 9-12
(Supplemental Virtual)
(Supplemental Virtual)
Total Students
466 students
Total Classroom Teachers
49 teachers
Year Founded
1966
Colors
Blue and Gold
School Rankings
Haddam-killingworth High School ranks within the top 30% of all 939 schools in Connecticut (based off of combined math and reading proficiency testing data).
The diversity score of Haddam-killingworth High School is 0.22, 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
#221 out of 939 schools
(Top 30%)
(Top 30%)
Math Test Scores (% Proficient)
55-59%
41%
Reading/Language Arts Test Scores (% Proficient)
70-74%
50%
Science Test Scores (% Proficient)
45-49%
47%
Student-Teacher Ratio
10:1
12:1
Asian
2%
5%
Hispanic
5%
32%
Black
1%
12%
White
88%
46%
Two or more races
4%
5%
All Ethnic Groups
Graduation Rate
≥95%
89%
Eligible for Free Lunch
11%
38%
Eligible for Reduced Lunch
2%
6%
School Statewide Testing
School District Name
Source: National Center for Education Statistics (NCES), CT Dept. of Education
School Notes
- School Mascot: Cougars
Frequently Asked Questions
What is Haddam-killingworth High School's ranking?
Haddam-killingworth High School is ranked #221 out of 939 schools, which ranks it among the top 30% of public schools in Connecticut.
What percent of students have achieved state testing proficiency in math and reading?
55-59% of students have achieved math proficiency (compared to the 41% CT state average), while 70-74% of students have achieved reading proficiency (compared to the 50% CT state average).
What is the graduation rate of Haddam-killingworth High School?
The graduation rate of Haddam-killingworth High School is 95%, which is higher than the Connecticut state average of 89%.
How many students attend Haddam-killingworth High School?
466 students attend Haddam-killingworth High School.
What is the racial composition of the student body?
88% of Haddam-killingworth High School students are White, 5% of students are Hispanic, 4% of students are Two or more races, 2% of students are Asian, and 1% of students are Black.
What is the student-teacher ratio of Haddam-killingworth High School?
Haddam-killingworth High School has a student ration of 10:1, which is lower than the Connecticut state average of 12:1.
What grades does Haddam-killingworth High School offer ?
Haddam-killingworth High School offers enrollment in grades 9-12 (Supplemental Virtual).
What school district is Haddam-killingworth High School part of?
Haddam-killingworth High School is part of Regional School District 17.
School Calendar
View the Haddam-killingworth High School yearly calendar below.
School Reviews
Review Haddam-killingworth High School. Reviews should be a few sentences in length. Please include any comments on:
- Quality of academic programs, teachers, and facilities
- Availability of music, art, sports and other extracurricular activities
Recent Articles
When “Free Public School” Still Isn’t Free
Discover the hidden costs of public school in 2026, from supplies and fees to transportation, technology, and extracurricular expenses.
What a District Budget Cut Means for Your Child's School Experience
Learn how district budget cuts can affect class sizes, programs, staffing, transportation, and your child's daily school experience in 2026.
School Closure Risk: What Parents Should Check Before Moving
Learn how parents can assess school closure risk before buying or renting in a district, using enrollment, funding, and boundary data.
