Chinook Middle School, Seatac WA

Original Research by School Decision on Chinook Middle School

Chinook Middle School serves sixth through eighth graders in SeaTac, part of the Highline Public Schools district. The school is a regular public school, not a charter or magnet institution. Enrollment is substantial for a middle school, and a large share of students qualify for free or reduced-price lunch, a marker of the community’s economic profile. The student body is highly diverse, with no single racial or ethnic group forming a majority; the largest groups are Hispanic students, followed by Black students, Asian students, Native Hawaiian or other Pacific Islander students, White students, and students identifying as two or more races.

State testing results from the most recent school year show that across all three grades and both math and English language arts, proficiency rates are low. In math, fewer than one in four students met the state standard in any grade, and the overall math proficiency rate across the school was under one in five. In English language arts, rates were somewhat higher but still below two out of five students scoring proficient. Science results for eighth graders, the only grade tested in that subject, showed just under a third of students proficient. Compared with other school districts in King County, Chinook’s overall proficiency index lands in the bottom quartile. Because only a single year of testing data was available, there is no trend to observe; a parent may want to ask the school about year-over-year patterns and any academic improvement efforts underway.

As a middle school, Chinook does not report a graduation rate, and the data provided includes no information on chronic absenteeism, discipline, course access, or staffing ratios. These are gaps a family might want to follow up on directly with the school or district. The school’s special education and English learner counts were also missing from the dataset.

SeaTac is a city organized around Seattle-Tacoma International Airport, which sits entirely within its boundaries. The built environment is heavily auto-oriented, shaped by wide arterials, hotel strips, and airport-related logistics. There is no traditional downtown; civic life is scattered. The city has seen steady population growth and is a designated regional growth center. Housing values and rents reflect the broader King County market, where the cost of owning or renting is high relative to national benchmarks. The city is a renter-majority housing market. Three light rail stations connect SeaTac to downtown Seattle and the University of Washington, offering some transit-oriented nodes amid the otherwise car-dependent landscape.

Highline Public Schools has been undertaking a multi-year school modernization program that includes rebuilding and relocating some schools. The district has also expanded its choice school options, including Innovation Heights Academy and Maritime High School, giving families alternative secondary pathways beyond their neighborhood school. These district-level changes may affect feeder patterns and school programming over time.

For a family considering Chinook Middle School, the picture is straightforward. The school serves a large, economically diverse student body in a community shaped by the airport economy. Academic performance on state assessments is low relative to other King County schools, which is a central fact a family would want to discuss with the school’s leadership. The absence of data on chronic absenteeism, staffing, and course access limits the fuller picture of the school environment. With the district actively building and opening new schools, families may also want to understand how Chinook fits into Highline’s evolving facilities and choice-school landscape.

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Academic performance

How students perform on state tests, by grade, set against the district.

Math

Grade 615%

School 15% · District 20% · ▼ 5 pts below district

▼ 22 pts below state median · ▼ 38 pts below county median

Grade 723%

School 23% · District 20% · ▲ 3 pts above district

▼ 15 pts below state median · ▼ 31 pts below county median

Grade 813%

School 13% · District 18% · ▼ 5 pts below district

▼ 20 pts below state median · ▼ 39 pts below county median

English language arts

Grade 627%

School 27% · District 30% · ▼ 3 pts below district

▼ 21 pts below state median · ▼ 33 pts below county median

Grade 737%

School 37% · District 31% · ▲ 7 pts above district

▼ 13 pts below state median · ▼ 26 pts below county median

Grade 837%

School 37% · District 33% · ▲ 4 pts above district

▼ 12 pts below state median · ▼ 28 pts below county median

Science

Grade 830%

School 30% · District 27% · ▲ 3 pts above district

▼ 12 pts below state median · ▼ 30 pts below county median

This schoolHighline School District, same grade

Graduation rate (ACGR) reflects the federally published Adjusted Cohort Graduation Rate for the most recent year available. We refresh this data annually at the close of each academic year in June. The federal source publishes a banded rate (for example, "90-94%") instead of an exact number for cohorts small enough to risk identifying individual students. The state distribution chart, where shown, plots every school in the state with a published rate or band; schools whose rate is federally suppressed are excluded. Where the federal source publishes a band rather than an exact rate, the school is placed within its band using a stable, ID-derived offset, so its position is consistent across visits.

Proficiency by household income

English language arts

Grade 5Lower-income30%Higher-income39%10 pp gap

Grade 6Lower-income20%Higher-income48%28 pp gap

Grade 7Lower-income31%Higher-income52%21 pp gap

Grade 8Lower-income37%Higher-income38%1 pp gap

Mathematics

Grade 5Lower-income5%Higher-income27%22 pp gap

Grade 6Lower-income10%Higher-income30%21 pp gap

Grade 7Lower-income18%Higher-income37%19 pp gap

Grade 8Lower-income11%Higher-income21%10 pp gap