Serving 2,563 students in grades 9-12, Diamond Bar High School ranks in the top 10% of all schools in California for overall test scores (math proficiency is top 10%, and reading proficiency is top 10%).
The percentage of students achieving proficiency in math is 68% (which is higher than the California state average of 34%). The percentage of students achieving proficiency in reading/language arts is 78% (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 95% of the student body (majority Asian), which is higher than the California state average of 80% (majority Hispanic and Asian).
Quick Facts (2026-27)
- Grades: 9-12
- Enrollment: 2,563 students
- Student-Teacher Ratio: 26:1
- Minority Enrollment: 95%
- Graduation Rate: 97% (Top 5% in CA)
- Overall Testing Rank: Top 10%
- Math Proficiency: 68% (Top 10%)
- Reading Proficiency: 78% (Top 10%)
- Science Proficiency: 47% (Top 20%)
- Attendance Zone: Diamond Bar High serves the southeast part of Diamond Bar, CA, covering an area of approximately 13.3 square miles. Most residents can expect a drive of 5 to 10 minutes to reach the school, with the furthest edge of the attendance zone located about 4.1 miles away.
- Source: National Center for Education Statistics (NCES), CA Dept. of Education
Top Rankings
Diamond Bar High School ranks among the top 20% of public schools in California for:
Category
Attribute
Overall Rank
Math Proficiency
Reading/Language Arts Proficiency
Science Proficiency
Graduation Rate
School Overview
Diamond Bar High School's student population of 2,563 students has stayed relatively flat over five school years.
The teacher population of 99 teachers has stayed relatively flat over five school years.
Grades Offered
Grades 9-12
Total Students
2,563 students
Total Classroom Teachers
99 teachers
Year Founded
1982
School Calendar
Campus Size
10 acres
Average Class Size
25 students
School Rankings
Diamond Bar High School ranks within the top 10% of all 9,523 schools in California (based off of combined math and reading proficiency testing data).
The diversity score of Diamond Bar High School is 0.45, 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
#618 out of 9523 schools
(Top 10%)
(Top 10%)
Math Test Scores (% Proficient)
68%
34%
Reading/Language Arts Test Scores (% Proficient)
78%
47%
Science Test Scores (% Proficient)
47%
29%
Student-Teacher Ratio
26:1
21:1
American Indian
n/a
1%
Asian
72%
12%
Hispanic
17%
56%
Black
1%
5%
White
5%
20%
Hawaiian
1%
n/a
Two or more races
4%
6%
All Ethnic Groups
Graduation Rate
97%
86.2%
Chronically Absent Students
(22-23)10.3%
27.7%
Eligible for Free Lunch
21%
54%
Eligible for Reduced Lunch
1%
8%
School Statewide Testing
School District Name
Sports
Colors
Purple, Gold
School Mascot
Brahma Bull
Source: National Center for Education Statistics (NCES), CA Dept. of Education
Frequently Asked Questions
What is Diamond Bar High School's ranking?
Diamond Bar High School is ranked #618 out of 9,523 schools, which ranks it among the top 10% of public schools in California.
What schools are Diamond Bar High School often compared to?
Diamond Bar High Schoolis often viewed alongside schools like Walnut High School, Diamond Ranch High School by visitors of our site.
What percent of students have achieved state testing proficiency in math and reading?
68% of students have achieved math proficiency (compared to the 34% CA state average), while 78% of students have achieved reading proficiency (compared to the 47% CA state average).
What is the graduation rate of Diamond Bar High School?
The graduation rate of Diamond Bar High School is 97%, which is higher than the California state average of 86.2%.
How many students attend Diamond Bar High School?
2,563 students attend Diamond Bar High School.
What is the racial composition of the student body?
72% of Diamond Bar High School students are Asian, 17% of students are Hispanic, 5% of students are White, 4% of students are Two or more races, 1% of students are Black, and 1% of students are Hawaiian.
What is the student-teacher ratio of Diamond Bar High School?
Diamond Bar High School has a student ration of 26:1, which is higher than the California state average of 21:1.
What grades does Diamond Bar High School offer ?
Diamond Bar High School offers enrollment in grades 9-12
What school district is Diamond Bar High School part of?
Diamond Bar High School is part of Walnut Valley Unified School District.
School Reviews
5 10/10/2025
Performing arts program is amazing. Orchestra is #1 in nation.
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