Enrollment by grade, 2024-25 school year, as reported to the WA State Board of Education.
Tuition and financial aid
Annual tuition
$47,900 (2026-27)
By division / fees
Preschool $22,500; PreK $25,100; K-4 $43,500; 5-8 $47,900. All-inclusive (no mandatory fees).
Financial aid
$1,025,700 total aid awarded; 9.5% of ~370 students receive grants; average grant $28,492.
Source: the school's own tuition page · aid page, observed 2026-07-03. Tuition changes annually — verify before applying.
Academics
Curriculum
PK-8; all-inclusive tuition model.
College matriculation
Publishes 'Beyond STS' page on graduates' secondary-school placements.
Washington private schools are not required to publish state assessment results, and this school's internal test data is not public. Unlike the public-school pages on this site, no score comparison is possible here — treat curriculum labels and matriculation lists as the available evidence.
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