Mercer Island High School
#21
Best ACT in Washington High Schools
1,524
Students
20.5:1
S:T Ratio
School Snapshot
Key metrics at a glance1,350
A
29
A
29
A+
37%
C+
21:1
B-
This Week at Mercer Island – September 20, 2026
204 students practicing on Varsity Tutors
Academic Resources
Typical courses and practice resources for students at Mercer Island High School
Standardized Test Dates
Upcoming national, state, and school calendar dates that affect students at Mercer Island High School.
National Tests
August 1, 2026 – November 30, 2026
ISEE — Fall Testing Season
August 3, 2026 – June 30, 2027
SSAT — Flex Testing
September 22, 2026
SAT — National
September 25, 2026
SAT — National
September 29, 2026
ACT — National
October 1, 2026 – October 30, 2026
PSAT 8/9 — Fall
State Assessments
January 25, 2027 – April 30, 2027
WA-AIM
January 25, 2027 – March 19, 2027
WIDA ACCESS
January 25, 2027 – March 19, 2027
WIDA Alternate ACCESS
March 1, 2027 – June 25, 2027
Smarter Balanced — Online
April 5, 2027 – May 14, 2027
Smarter Balanced — Paper/Pencil
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1:1 Tutoring
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9100 Se 42nd, Mercer Island, WA 98040
(206)236-3345
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Mercer Island School District