Chaffey High School is a public high school in Ontario, California, United States. It is part of the Chaffey Joint Union High School District and rests on approximately 65 acres, making it one of the largest high schools by area in California. The school currently serves northern Ontario and southern Rancho Cucamonga.
Serving 3,127 students in grades 9-12, Chaffey High School ranks in the bottom 50% of all schools in California for overall test scores (math proficiency is bottom 50%, and reading proficiency is bottom 50%).
The percentage of students achieving proficiency in math is 18% (which is lower than the California state average of 34%). The percentage of students achieving proficiency in reading/language arts is 54% (which is higher than the California state average of 47%).
The student-teacher ratio of 23:1 is higher than the California state level of 21:1.
Minority enrollment is 97% of the student body (majority Hispanic), which is higher than the California state average of 80% (majority Hispanic).
Quick Facts (2026)
- Grades: 9-12
- Enrollment: 3,127 students
- Student-Teacher Ratio: 23:1
- Minority Enrollment: 97%
- Graduation Rate: 84% (Btm 50% in CA)
- Overall Testing Rank: Bottom 50%
- Math Proficiency: 18% (Btm 50%)
- Reading Proficiency: 54% (Top 30%)
- Science Proficiency: 17% (Btm 50%)
- Source: National Center for Education Statistics (NCES), CA Dept. of Education
School Overview
Chaffey High School's student population of 3,127 students has declined by 7% over five school years.
The teacher population of 134 teachers has stayed relatively flat over five school years.
Grades Offered
Grades 9-12
Total Students
3,127 students
Total Classroom Teachers
134 teachers
Year Founded
1911
Colors
Black, Orange
School Rankings
Chaffey High School ranks within the bottom 50% of all 9,523 schools in California (based off of combined math and reading proficiency testing data).
The diversity score of Chaffey High School is 0.21, which is less 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
#4830 out of 9523 schools
(Bottom 50%)
(Bottom 50%)
Math Test Scores (% Proficient)
18%
34%
Reading/Language Arts Test Scores (% Proficient)
54%
47%
Science Test Scores (% Proficient)
17%
29%
Student-Teacher Ratio
23:1
21:1
American Indian
1%
1%
Asian
2%
12%
Hispanic
89%
56%
Black
3%
5%
White
3%
20%
Hawaiian
n/a
n/a
Two or more races
2%
6%
All Ethnic Groups
Graduation Rate
84%
87%
Eligible for Free Lunch
70%
54%
Eligible for Reduced Lunch
11%
8%
School Statewide Testing
School District Name
Source: National Center for Education Statistics (NCES), CA Dept. of Education
Frequently Asked Questions
What is Chaffey High School's ranking?
Chaffey High School is ranked #4830 out of 9,523 schools, which ranks it among the bottom 50% of public schools in California.
What schools are Chaffey High School often compared to?
Chaffey High Schoolis often viewed alongside schools like Colony High School by visitors of our site.
What percent of students have achieved state testing proficiency in math and reading?
18% of students have achieved math proficiency (compared to the 34% CA state average), while 54% of students have achieved reading proficiency (compared to the 47% CA state average).
What is the graduation rate of Chaffey High School?
The graduation rate of Chaffey High School is 84%, which is lower than the California state average of 87%.
How many students attend Chaffey High School?
3,127 students attend Chaffey High School.
What is the racial composition of the student body?
89% of Chaffey High School students are Hispanic, 3% of students are Black, 3% of students are White, 2% of students are Asian, 2% of students are Two or more races, and 1% of students are American Indian.
What is the student-teacher ratio of Chaffey High School?
Chaffey High School has a student ration of 23:1, which is higher than the California state average of 21:1.
What grades does Chaffey High School offer ?
Chaffey High School offers enrollment in grades 9-12
What school district is Chaffey High School part of?
Chaffey High School is part of Chaffey Joint Union High School District.
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