Los Osos High School is a public high school located in the city of Rancho Cucamonga in Southern California's Inland Empire in the United States. It operates as part of the Chaffey Joint Union High School District.
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 52% (which is higher than the California state average of 33%). 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 25:1 is higher than the California state level of 21:1.
Minority enrollment is 73% of the student body (majority Hispanic), which is lower than the California state average of 80% (majority Hispanic).
Quick Stats (2025)
- Grades: 9-12
- Enrollment: 2,759 students
- Student:Teacher Ratio: 25:1
- Minority Enrollment: 73%
- Graduation Rate: 96% (Top 10% in CA)
- Overall Testing Rank: Top 20%
- Math Proficiency: 52% (Top 20%)
- Reading Proficiency: 81% (Top 5%)
- Science Proficiency: 35% (Top 50%)
- 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
Graduation Rate
Diversity
School Overview
Los Osos High School's student population of 2,759 students has declined by 9% over five school years.
The teacher population of 111 teachers has declined by 9% over five school years.
Grades Offered
Grades 9-12
Total Students
2,759 students
Gender %
Total Classroom Teachers
111 teachers
Year Founded
2002
Colors
White, Navy Blue, Gold, Carolina blue
School Rankings
Los Osos High School ranks within the top 20% of all 9,602 schools in California (based off of combined math and reading proficiency testing data).
The diversity score of Los Osos High School is 0.71, 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
#1005 out of 9602 schools
(Top 20%)
(Top 20%)
Math Test Scores (% Proficient)
52%
33%
Reading/Language Arts Test Scores (% Proficient)
81%
47%
Science Test Scores (% Proficient)
35%
29%
Student : Teacher Ratio
25:1
21:1
American Indian
n/a
1%
Asian
22%
12%
Hispanic
41%
56%
Black
6%
5%
White
27%
20%
Hawaiian
n/a
n/a
Two or more races
4%
6%
All Ethnic Groups
Graduation Rate
96%
87%
Eligible for Free Lunch
31%
54%
Eligible for Reduced Lunch
3%
8%
School Statewide Testing
School District Name
Source: National Center for Education Statistics (NCES), CA Dept. of Education
Profile last updated: 02/09/2025
Frequently Asked Questions
What is Los Osos High School's ranking?
Los Osos High School is ranked #1005 out of 9,602 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?
52% of students have achieved math proficiency (compared to the 33% 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 96%, which is higher than the California state average of 87%.
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, 27% of students are White, 22% of students are Asian, 6% of students are Black, and 4% 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 25:1, 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 Calendar
View the Los Osos High School yearly calendar below.
School Reviews
5 5/1/2012
Oustanding, both of my children attended this school
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