Serving 2,759 students in grades 9-12, Los Osos High School ranks in the top 20% of all schools in California for overall test scores (math proficiency is top 20%, and reading proficiency is top 20%).
The percentage of students achieving proficiency in math is 51% (which is higher than the California state average of 34%). The percentage of students achieving proficiency in reading/language arts is 81% (which is higher than the California state average of 47%).
The student-teacher ratio of 26:1 is higher than the California state level of 21:1.
Minority enrollment is 75% of the student body (majority Hispanic), which is lower than the California state average of 80% (majority Hispanic).
Quick Facts (26-27)
- Grades: 9-12
- Enrollment: 2,759 students
- Student-Teacher Ratio: 26:1
- Minority Enrollment: 75%
- Graduation Rate: 95% (Top 30% in CA)
- Overall Testing Rank: Top 20%
- Math Proficiency: 51% (Top 20%)
- Reading Proficiency: 81% (Top 5%)
- Science Proficiency: 35% (Top 50%)
- Attendance Zone: Los Osos High serves the northern part of Rancho Cucamonga, CA, encompassing an area of approximately 29.9 square miles. Most families can expect a typical drive to the school of about 5-10 minutes, with the furthest edge of the attendance zone reaching up to 6.1 miles away.
- Source: National Center for Education Statistics (NCES), CA Dept. of Education
Top Rankings
Los Osos High School ranks among the top 20% of public schools in California for:
Category
Attribute
Overall Rank
Math Proficiency
Reading/Language Arts Proficiency
School Overview
Los Osos High School's student population of 2,759 students has declined by 6% over five school years.
The teacher population of 107 teachers has declined by 8% over five school years.
Grades Offered
Grades 9-12
Total Students
2,759 students
Showing 2015–2025. Full 23-year historical data available below ↓
Total Classroom Teachers
107 teachers
Showing 2014–2025. Full 23-year historical data available below ↓
Year Founded
2002
School Calendar
Campus Size
30 acres
School Motto
Where Excellence is a Habit
School Rankings
Los Osos High School ranks within the top 20% of all 9,523 schools in California (based off of combined math and reading proficiency testing data).
The diversity score of Los Osos High School is 0.72, which is more than the diversity score at state average of 0.63. The school's diversity has stayed relatively flat over five school years.
Overall Testing Rank
#1106 out of 9523 schools
(Top 20%)
(Top 20%)
Showing 2013–2023. Full 14-year historical data available below ↓
Math Test Scores (% Proficient)
51%
34%
Showing 2013–2023. Full 14-year historical data available below ↓
Reading/Language Arts Test Scores (% Proficient)
81%
47%
Showing 2012–2022. Full 13-year historical data available below ↓
Science Test Scores (% Proficient)
35%
29%
Student-Teacher Ratio
26:1
21:1
Showing 2014–2025. Full 23-year historical data available below ↓
Asian
23%
12%
Showing 2015–2025. Full 23-year historical data available below ↓
Hispanic
41%
56%
Showing 2015–2025. Full 23-year historical data available below ↓
Black
6%
5%
Showing 2015–2025. Full 23-year historical data available below ↓
White
25%
20%
Showing 2015–2025. Full 23-year historical data available below ↓
Two or more races
5%
6%
Showing 2015–2025. Full 17-year historical data available below ↓
All Ethnic Groups
Showing 2015–2025. Full 23-year historical data available below ↓
Graduation Rate
95%
86.2%
Showing 2014–2023. Full 13-year historical data available below ↓
Chronically Absent Students
(22-23)19.3%
27.7%
Eligible for Free Lunch
30%
54%
Showing 2015–2025. Full 23-year historical data available below ↓
Eligible for Reduced Lunch
14%
8%
Showing 2015–2025. Full 23-year historical data available below ↓
School Statewide Testing
School District Name
Sports
Colors
White, Navy Blue, Gold, Carolina blue
School Mascot
Grizzlies
Source: National Center for Education Statistics (NCES), CA Dept. of Education
Frequently Asked Questions
What is Los Osos High School's ranking?
Los Osos High School is ranked #1106 out of 9,523 schools, which ranks it among the top 20% of public schools in California.
What schools are Los Osos High School often compared to?
Los Osos High Schoolis often viewed alongside schools like Rancho Cucamonga High School by visitors of our site.
What percent of students have achieved state testing proficiency in math and reading?
51% of students have achieved math proficiency (compared to the 34% CA state average), while 81% of students have achieved reading proficiency (compared to the 47% CA state average).
What is the graduation rate of Los Osos High School?
The graduation rate of Los Osos High School is 95%, which is higher than the California state average of 86.2%.
How many students attend Los Osos High School?
2,759 students attend Los Osos High School.
What is the racial composition of the student body?
41% of Los Osos High School students are Hispanic, 25% of students are White, 23% of students are Asian, 6% of students are Black, and 5% of students are Two or more races.
What is the student-teacher ratio of Los Osos High School?
Los Osos High School has a student ration of 26:1, which is higher than the California state average of 21:1.
What grades does Los Osos High School offer ?
Los Osos High School offers enrollment in grades 9-12
What school district is Los Osos High School part of?
Los Osos High School is part of Chaffey Joint Union High School District.
School Reviews
5 10/10/2025
Oustanding, both of my children attended this school
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