Mercer Island High School
🇺🇸 Official data · 2025Mercer Island, Washington 98040 · Mercer Island School District
#2 of 333 high schools in Washington
#477 of 16,910 nationally
About Mercer Island High School
Mercer Island High School is a public high located in Mercer Island, in the Mercer Island School District school district of Washington, United States. It caters for Grades 9–12. In 2025 it enrolled 1,439 students. Traditional public schools run by a school district; free to attend.
Its Success Index (US) is 86.7 out of 100, placing it in the top 5% of high schools in United States and 2nd of 333 ranked high schools in Washington. Its strongest component is reading proficiency (100th percentile), and its weakest is students per teacher (23th percentile).
Other published figures: enrollment 1,439.
There are 6 schools in Mercer Island; Mercer Island High School ranks 4th of 6 scored schools there.
Success Index (US) breakdown
Each component is a percentile against high schools across United States.
- Math proficiency (30%)90%
- Reading proficiency (30%)99.5%
- Community advantage (fewer free/reduced-price lunch) (25%)7.1%
- Students per teacher (15%)18.9
The Success Index (US) summarises published data about a school community. It is not a measure of teaching quality. Read the methodology.
Published measures
All figures published for Mercer Island High School by the official sources.
- Enrollment
- 1,439
- Students enrolled in the latest NCES directory year.
- Free/reduced-price lunch
- 7.1%
- Share of students eligible for free or reduced-price lunch.
- Students per teacher
- 18.9
- Enrollment divided by FTE teachers; not class size.
- Reading proficiency
- 99.5%
- Share of tested students proficient or above (all students, all grades).
- Math proficiency
- 90%
- Share of tested students proficient or above (all students, all grades).
Free academic assessment
Is your child on grade level in reading and math?
Success Tutoring offers personalised English and math tutoring from Kindergarten to Grade 12. Start with a free online assessment and a clear plan for the year ahead.
- Personalised learning plan mapped to the Australian Curriculum
- English & Maths from Kindergarten to Year 12
- Flexible memberships, no lock-in contracts
- Centres across NSW, VIC, QLD, WA, SA and ACT
Schools near Mercer Island High School
Closest schools by straight-line distance, with their Success Index (US).
Northwood Elementary School
Mercer Island · Public elementary · Grades PK–5
398 students · 365 m away
West Mercer Elementary
Mercer Island · Public elementary · Grades K–5
431 students · 886 m away
Island Park Elementary
Mercer Island · Public elementary · Grades K–5
364 students · 2.0 km away
Enatai Elementary School
Bellevue · Public elementary · Grades PK–5
518 students · 2.5 km away
Newport Heights Elementary
Bellevue · Public elementary · Grades PK–5
549 students · 3.4 km away
Newport Senior High School
Bellevue · Public high · Grades 9–12
1,850 students · 3.6 km away
Islander Middle School
Mercer Island · Public middle · Grades 6–8
960 students · 3.9 km away
Bellevue High School
Bellevue · Public high · Grades 9–12
1,683 students · 3.9 km away
Woodridge Elementary
Bellevue · Public elementary · Grades PK–5
554 students · 4.1 km away
Vera Risdon Middle School
Newcastle · Public middle · Grades 6–8
751 students · 4.3 km away
Similar schools
Public high schools in Washington with a comparable Enrollment.
Inglemoor HS
Kenmore · Public high · Grades 9–12
1,441 students
Shadle Park High School
Spokane · Public high · Grades 9–12
1,445 students
Evergreen High School
Vancouver · Public high · Grades 9–12
1,427 students
Highline High School
Burien · Public high · Grades 9–12
1,423 students
Shelton High School
Shelton · Public high · Grades 9–12
1,455 students
Mountlake Terrace High School
Mtlk Terrace · Public high · Grades 9–12
1,456 students
Frequently asked questions
Is Mercer Island High School a good school?
Mercer Island High School has a Success Index (US) of 86.7 out of 100 (Top 5% of high schools in United States) and ranks #2 of 333 in Washington. The index summarises published data about the school community and, where available, attainment; it does not measure teaching quality, so visit the school and ask about support at your child's level.
Where does Mercer Island High School rank in Washington?
Mercer Island High School ranks #2 of 333 high schools in Washington and #477 of 16,910 nationally on the Success Index (US) (2025 data).
How many students attend Mercer Island High School?
Mercer Island High School had 1,439 students in 2025.
Is Mercer Island High School a elementary school or a high school?
Mercer Island High School is classified as a high covering Grades 9–12. It is a public school.
What other schools are near Mercer Island High School?
There are 10 schools within 15 km of Mercer Island High School; they are listed on this page with their Success Index (US) and distance, and can be compared side by side.