Serving 2,172 students in grades 9-12, Mount Si High School ranks in the top 10% of all schools in Washington for overall test scores (math proficiency is top 20%, and reading proficiency is top 20%).
The percentage of students achieving proficiency in math is 59% (which is higher than the Washington state average of 40%). The percentage of students achieving proficiency in reading/language arts is 89% (which is higher than the Washington state average of 53%).
The student:teacher ratio of 22:1 is higher than the Washington state level of 16:1.
Minority enrollment is 29% of the student body (majority Hispanic and Asian), which is lower than the Washington state average of 52% (majority Hispanic).
Quick Stats (2025)
Grades: 9-12
Enrollment: 2,172 students
Student:Teacher Ratio: 22:1
Minority Enrollment: 29%
Graduation Rate
: 97% (Top 1% in WA)
Overall Testing Rank
: Top 10%
Math Proficiency
: 59% (Top 20%)
Reading Proficiency
: 89% (Top 5%)
Science Proficiency
: 82% (Top 5%)
Source: National Center for Education Statistics (NCES), WA Dept. of Education
Mount Si High School ranks within the top 10% of all 2,113 schools in Washington (based off of combined math and reading proficiency testing data).
The diversity score of Mount Si High School is 0.48, which is less than the diversity score at state average of 0.69. The school's diversity has stayed relatively flat over five school years.
Mount Si High School is ranked #159 out of 2,113 schools, which ranks it among the top 10% of public schools in Washington.
What percent of students have achieved state testing proficiency in math and reading?
59% of students have achieved math proficiency (compared to the 40% WA state average), while 89% of students have achieved reading proficiency (compared to the 53% WA state average).
What is the graduation rate of Mount Si High School?
The graduation rate of Mount Si High School is 97%, which is higher than the Washington state average of 84%.
How many students attend Mount Si High School?
2,172 students attend Mount Si High School.
What is the racial composition of the student body?
71% of Mount Si High School students are White, 11% of students are Hispanic, 9% of students are Asian, 7% of students are Two or more races, 1% of students are American Indian, and 1% of students are Black.
What is the student:teacher ratio of Mount Si High School?
Mount Si High School has a student ration of 22:1, which is higher than the Washington state average of 16:1.
What grades does Mount Si High School offer ?
Mount Si High School offers enrollment in grades 9-12 (offers virtual instruction).
What school district is Mount Si High School part of?
We explore how the Department of Education shapes American education, from its cabinet-level leadership to its impact on millions of students, written for general audiences seeking clarity on this vital institution.
Explore the origins of educational segregation during the colonial era and the differential treatment of Native American, African American, and white students. This article delves into the historical context, policies, and societal attitudes that shaped early education in colonial America, highlighting the disparities and injustices that persisted within the schooling systems of that time.
Explore the revolutionary approach of Personalized Learning in K-12 education. This article discusses the benefits, challenges, and potential of tailoring education to individual student needs, incorporating technology and adaptive learning methods to prepare students for the 21st century.
Quick Stats (2025)
Grades: 9-12
Enrollment: 2,172 students
Student:Teacher Ratio: 22:1
Minority Enrollment: 29%
Graduation Rate
: 97% (Top 1%)
Overall Testing Rank
: Top 10%
Math Proficiency
: 59% (Top 20%)
Reading Proficiency
: 89% (Top 5%)
Science Proficiency
: 82% (Top 5%)
Source: National Center for Education Statistics (NCES), WA Dept. of Education
Related School Videos
5:18
1:11
7:38
2:40
Related School News
Things are off to a hot start for the Mount Si football team ... fastest times in school history ...
He described the new challenges as remote learning kicked off his freshman year at Mount Si High ...
The portable classrooms which sat outside of Mount Si High School were moved to the high school's Freshman Campus last Thursday, to clear the way for construction ...
