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Oldest Private High Schools in Colorado

The average private high school in Colorado was founded around 1978 (2026).

The oldest private high school in Colorado is St. Mary's Academy, founded in 1864.

Quick Facts (2026)

# CO Schools Ranked: 98
Top 20 Range (Year Founded): 1864–1962
CO School Avg.: 1977
National School Avg.: 1967

Quick Facts (2026)

# CO Schools Ranked: 98
Top 20 Range (Year Founded): 1864–1962
CO School Avg.: 1977
National School Avg.: 1967

Frequently Asked Questions

What is the Colorado average private high schools founding year?

The Colorado average private high schools founding year is 1978 for 2026.

What are the private high schools with oldest founding year in Colorado?

The top ranked private high schools in Colorado include St. Mary's Academy, Regis Jesuit High School and St. Mary's High School.

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