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Best Oregon Private High Schools Belonging to National Association of Independent Schools (NAIS) (2026)

For the 2026 school year, there are 6 private high schools belonging to National Association of Independent Schools (NAIS) serving 2,794 students in Oregon. You can also find more schools membership associations in Oregon.

The private high schools belonging to National Association of Independent Schools (NAIS) in Oregon include Cascades Academy, Catlin Gabel School, and The Delphian School.

The average acceptance rate is 54%, which is lower than the Oregon private high school average acceptance rate of 83%.

33% of private high schools belonging to National Association of Independent Schools (NAIS) in Oregon are religiously affiliated (most commonly Episcopal and Catholic).

The Delphian School Photo - Delphian is on 720 acres in the beautiful coastal mountains of the Pacific Northwest in Oregon. Here teachers don't lecture in front of a blackboard while students frantically take notes. At our school, students learn at their own pace and study independently with a personalized program that is specifically designed to satisfy their specific needs and interests.

Catlin Gabel School Photo - Athletes, artists, scientists, and scholars all find a place in our community, and success after graduation. Most students go on to attend a 4-year college or university of their choosing, with 97%+ reporting satisfaction with their post-graduation plans.

Cascades Academy Photo - This year marks Cascades Academy's 20th anniversary, and our school is thriving. With a stable foundation in place, we're able to reflect on the challenges and growth we've experienced over the past two decades, and look to the future while creating a vision for the next 20 years. Our faculty and staff took time earlier this year to update our

Oregon Episcopal School Photo - The OES science program challenges students through independent research, professional mentoring, and national and international competition.

Top-Ranked Private High Schools Belonging to National Association of Independent Schools (NAIS) in Oregon (2026)

School

Location

Quick Facts

Catlin Gabel School

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8825 SW Barnes Road
Portland, OR 97225
(503) 297-1894

Gr: PK-12 | 788 students Avg. class size: 15 students Sports: 8 | Extracurrculars: 35 Tuition & acceptance rate listed

The Delphian School

Alternative School

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(6)

20950 South West Rock Creek Road
Sheridan, OR 97378
(503) 843-3521

Gr: K-12 | 229 students Avg. class size: 13 students Sports: 6 | Extracurrculars: 36 Tuition & acceptance rate listed

Oregon Episcopal School

(Episcopal)

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(5)

6300 SW Nicol Road
Portland, OR 97223
(503) 768-3115

Gr: PK-12 | 861 students Avg. class size: 16 students Sports: 10 | Extracurrculars: 59 Tuition listed

Cascades Academy

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19860 Tumalo Reservoir Road
Bend, OR 97703
(541) 382-0699

Gr: PK-12 | 256 students Avg. class size: 18 students Sports: 8 | Extracurrculars: 11 Tuition & acceptance rate listed

St. Mary's Of Medford

(Catholic)

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(1)

816 Black Oak Drive
Medford, OR 97504
(541) 773-7877

Gr: 5-12 | 529 students Avg. class size: 18 students Sports: 13 | Extracurrculars: 16 Tuition listed

Mt. Scott Park Center For Learning

Alternative School

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6148 Se Holgate Blvd
Portland, OR 97206
(503) 771-8880

Gr: 9-12 | 131 students

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