Mullen High School
Independent Catholic school · Grades 9–12
Denver, CO
3601 S Lowell Blvd, Denver, CO 80236
Overall grade: A+
ChooseAPrivateSchool.com grade, from official facts compared with similar schools.
- B+Class size
- ACollege-going
- A-Years serving families
- A-Diversity
What stands out
- The largest of 47 Catholic schools in Colorado
- The largest Catholic school in Denver
- 98% of graduates go to four-year colleges
- Serving families in Denver since at least 2011
Mullen High School is an independent Catholic school in Denver, Colorado, for students from 9th grade through 12th grade. It has about 753 students and around 13 students per teacher. Its enrollment has held steady since 2011–12. The school is part of the Archdiocese of Denver. The school reports that about 98% of its graduates go on to four-year colleges. Students attend about 7 hours a day, 174 days a year.
At a glance
- Grades
- Grades 9–12
- Students
- 753
- Teachers
- 57.6 (full-time equivalent)
- Students per teacher
- 13.1
- Boys and girls
- Coed · 349 girls, 404 boys
- Religious affiliation
- Catholic · Independent Catholic school
- Diocese
- Archdiocese of Denver
- School day
- About 7 hours
- School year
- 174 days
- Graduates going to 4-year colleges
- About 98% (the school's estimate for the class before the survey)
Reviews
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How it compares
- Larger than 82% of Catholic high schools nationwide.
- Compared with 773 Catholic high schools nationwide.
Students by survey year
Total students reported in official records since 2011–12.
Students by grade
Student body
Member of
- National Catholic Educational Association
Questions to ask on a tour
- What is tuition, and what does it include (books, fees, uniforms, trips)?
- Do you offer financial aid, sibling discounts or payment plans?
- Do you accept ESA, voucher or tax-credit scholarship funds?
- How big are classes in my child's grade?
- What support is there for students who need extra help or more challenge?
- Is the school accredited, and by whom?
- What do a typical day and a typical week look like?
- How does the school communicate with families?
Questions about Mullen High School
What grades does Mullen High School serve?
Mullen High School serves grades 9–12.
How many students attend Mullen High School?
About 753 students, with 13 students per teacher, according to official records.
How much is tuition at Mullen High School?
Call the school to ask about tuition, financial aid and payment plans.
Official record · Updated October 2026 · Official search · Something wrong? Tell us
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