WashingtonSchoolsMercer Island High School

Mercer Island High School

PublicRegularGrades 912
Mercer Island, Washington · Mercer Island School District
SCHOOL SNAPSHOT
Students1,439
Student:Teacher18.9:1
Free/Reduced Lunch7%
Title INo

Academic Performance

State accountability indicators and test performance.

WA WSIF · 2025
WA WSIF 2025: Foundational

Performance indicators

proficiency_ela_decile
10
proficiency_math_decile
9
proficiency_combined_decile
9.5
grad_combined_decile
10
el_progress_decile
9
regularattendance_decile
7
ninthgradeontrack_decile
10
dualcredit_decile
9
sqss_combined_decile
8.666666
_2025_score
9.6
overall
Foundational

Source: California Department of Education — School Dashboard 2025 release.

Student test scores

Percentage of students who met or exceeded the grade-level standard on the most recent state assessment. Each tile is colour-coded: green ≥50%, amber 35-49%, red <35%.

ELA · SBA

Grade 10
93%
n=362
Overall
93%
n=362

Math · SBA

Grade 10
87%
n=361
Overall
87%
n=361

Source: SBA 2024. “Proficient” includes students who met or exceeded the standard; small-cell data (fewer than ~10 students) is suppressed by the state and shown as “—”.

How this state measures performance

State-specific testing and accountability details will appear here once the WA Department of Education data ingest completes.