Mercer Island High School

9100 SE 42nd, Mercer Island, WA 98040

ASchola Grade
Grades
9–12
High
Students
1,439
Enrolled 2024–25
Students per teacher
18.8 : 1
Full-time teachers
District
Mercer Island School District
King County

Schola Grade A · Excellent

Letter grade (A–F) · compared with 338 Washington high schools · How we grade
Test scores88% proficient in math & reading
100thpercentile
Equity80% of low-income students proficient
100thpercentile
Attendance8% chronically absent
99thpercentile
Graduation rate94% graduate in 4 years
74thpercentile
College readinessAt least 49% take AP, IB or dual-enrollment courses
77thpercentile
Class size18.8 students per teacher
65thpercentile

Percentiles compare this school with other Washington high schools; the line marks the middle. Data: test scores 2021–22, graduation and absenteeism 2022–23 (U.S. Department of Education, EDFacts); coursework 2023–24 (Civil Rights Data Collection); staffing 2024–25 (NCES).

About Mercer Island High School

Mercer Island High School is a public high school in Mercer Island, Washington, serving grades 9–12. It is part of Mercer Island School District. The school is located in a large suburb in King County.

In the 2024–25 school year, 1,439 students were enrolled, with about 18.8 students for every full-time teacher. That ratio is close to the typical Washington high school (19.2 students per teacher). Its Schola Grade is A (excellent), compared with 338 Washington high schools.

Grades & enrollment

Students per grade, 2024–25Grades 9–12

Location & nearby schools

9100 SE 42nd
Mercer Island, WA 98040
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School details

Type
Public School · What this means
Level
High
Grades offered
9–12
Enrollment (2024–25)
1,439 students
Students per teacher
18.8 to 1
AP courses offered
36
Charter school
No
Magnet school
No
Virtual learning
Offers virtual courses
Locale
Suburb — Large
School district
Mercer Island School District
County
King County
NCES school ID
530498000761

Schools near Mercer Island High School

All 13 schools in Mercer Island →

School data comes from the U.S. Department of Education: the National Center for Education Statistics (NCES) Common Core of Data and EDGE school locations (2024–25) and Private School Survey (2023–24), the Civil Rights Data Collection (2023–24), and EDFacts (test results 2021–22; graduation and chronic absenteeism 2022–23), plus other public sources. Please contact the school to confirm enrollment, programs, and other details. How we source data.