Los Osos High
🇺🇸 Official data · 2025Rancho Cucamonga, California 91737 · Chaffey Joint Union High
#186 of 1,343 high schools in California
#4810 of 16,910 nationally
About Los Osos High
Los Osos High is a public high located in Rancho Cucamonga, in the Chaffey Joint Union High school district of California, United States. It caters for Grades 9–12. In 2025 it enrolled 2,759 students. Traditional public schools run by a school district; free to attend.
Its Success Index (US) is 63.9 out of 100, placing it in the top 50% of high schools in United States and 186th of 1,343 ranked high schools in California. Its strongest component is reading proficiency (86th percentile), and its weakest is students per teacher (3th percentile).
Other published figures: enrollment 2,759.
There are 13 schools in Rancho Cucamonga; Los Osos High ranks 2nd of 13 scored schools there.
Success Index (US) breakdown
Each component is a percentile against high schools across United States.
- Math proficiency (30%)58%
- Reading proficiency (30%)81%
- Community advantage (fewer free/reduced-price lunch) (25%)43.7%
- Students per teacher (15%)25.8
The Success Index (US) summarises published data about a school community. It is not a measure of teaching quality. Read the methodology.
Published measures
All figures published for Los Osos High by the official sources.
- Enrollment
- 2,759
- Students enrolled in the latest NCES directory year.
- Free/reduced-price lunch
- 43.7%
- Share of students eligible for free or reduced-price lunch.
- Students per teacher
- 25.8
- Enrollment divided by FTE teachers; not class size.
- Reading proficiency
- 81%
- Share of tested students proficient or above (all students, all grades).
- Math proficiency
- 58%
- Share of tested students proficient or above (all students, all grades).
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Schools near Los Osos High
Closest schools by straight-line distance, with their Success Index (US).
Caryn Elementary
Alta Loma · Public elementary · Grades K–5
553 students · 622 m away
Banyan Elementary
Alta Loma · Public elementary · Grades K–6
572 students · 1.0 km away
Rancho Cucamonga High
Rancho Cucamonga · Public high · Grades 9–12
3,221 students · 1.8 km away
Victoria Groves Elementary
Alta Loma · Public elementary · Grades K–6
452 students · 1.9 km away
Carleton P. Lightfoot Elementary
Alta Loma · Public elementary · Grades K–5
878 students · 2.0 km away
John L. Golden Elementary
Etiwanda · Public elementary · Grades K–5
916 students · 2.1 km away
Day Creek Intermediate
Etiwanda · Public middle · Grades 6–8
1,326 students · 2.2 km away
Vineyard Junior High
Alta Loma · Public middle · Grades 6–8
933 students · 2.5 km away
Hermosa Elementary
Alta Loma · Public elementary · Grades K–6
442 students · 2.6 km away
Windrows Elementary
Etiwanda · Public elementary · Grades K–5
593 students · 2.7 km away
Similar schools
Public high schools in California with a comparable Enrollment.
Yucaipa High
Yucaipa · Public high · Grades 9–12
2,755 students
Mission Hills High
San Marcos · Public high · Grades 9–12
2,751 students
Chino Hills High
Chino Hills · Public high · Grades 9–12
2,748 students
Cajon High
San Bernardino · Public high · Grades 9–12
2,748 students
Dublin High
Dublin · Public high · Grades 9–12
2,771 students
Calexico High
Calexico · Public high · Grades 9–12
2,746 students
Frequently asked questions
Is Los Osos High a good school?
Los Osos High has a Success Index (US) of 63.9 out of 100 (Top 50% of high schools in United States) and ranks #186 of 1,343 in California. The index summarises published data about the school community and, where available, attainment; it does not measure teaching quality, so visit the school and ask about support at your child's level.
Where does Los Osos High rank in California?
Los Osos High ranks #186 of 1,343 high schools in California and #4810 of 16,910 nationally on the Success Index (US) (2025 data).
How many students attend Los Osos High?
Los Osos High had 2,759 students in 2025.
Is Los Osos High a elementary school or a high school?
Los Osos High is classified as a high covering Grades 9–12. It is a public school.
What other schools are near Los Osos High?
There are 10 schools within 15 km of Los Osos High; they are listed on this page with their Success Index (US) and distance, and can be compared side by side.