Mount Diablo High School is a public high school located in Concord, California, United States. It is the oldest school in the Mount Diablo Unified School District, founded in April 1901. The school currently serves western Concord, the unincorporated communities of Bay Point and Clyde and a portion of Pittsburg.
Serving 1,397 students in grades 9-12, Mt. Diablo 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 13% (which is lower than the California state average of 34%). The percentage of students achieving proficiency in reading/language arts is 27% (which is lower than the California state average of 47%).
The student-teacher ratio of 20:1 is lower than the California state level of 21:1.
Minority enrollment is 95% 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: 1,397 students
- Student-Teacher Ratio: 20:1
- Minority Enrollment: 95%
- Graduation Rate: 78% (Btm 50% in CA)
- Overall Testing Rank: Bottom 50%
- Math Proficiency: 13% (Btm 50%)
- Reading Proficiency: 27% (Btm 50%)
- Science Proficiency: 14% (Btm 50%)
- Source: National Center for Education Statistics (NCES), CA Dept. of Education
School Overview
Mt. Diablo High School's student population of 1,397 students has declined by 10% over five school years.
The teacher population of 71 teachers has declined by 8% over five school years.
Grades Offered
Grades 9-12
Total Students
1,397 students
Total Classroom Teachers
71 teachers
Year Founded
1901
Colors
Crimson and green
School Calendar
Campus Size
10 acres
School Rankings
Mt. Diablo 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 Mt. Diablo High School is 0.44, 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
#8025 out of 9523 schools
(Bottom 50%)
(Bottom 50%)
Math Test Scores (% Proficient)
13%
34%
Reading/Language Arts Test Scores (% Proficient)
27%
47%
Science Test Scores (% Proficient)
14%
29%
Student-Teacher Ratio
20:1
21:1
American Indian
n/a
1%
Asian
8%
12%
Hispanic
74%
56%
Black
8%
5%
White
5%
20%
Hawaiian
1%
n/a
Two or more races
4%
6%
All Ethnic Groups
Graduation Rate
78%
87%
Eligible for Free Lunch
70%
54%
Eligible for Reduced Lunch
10%
8%
School Statewide Testing
School District Name
Source: National Center for Education Statistics (NCES), CA Dept. of Education
School Notes
- School Mascot: Danny The Devil
Frequently Asked Questions
What is Mt. Diablo High School's ranking?
Mt. Diablo High School is ranked #8025 out of 9,523 schools, which ranks it among the bottom 50% of public schools in California.
What schools are Mt. Diablo High School often compared to?
Mt. Diablo High Schoolis often viewed alongside schools like Concord High School, Ygnacio Valley High School, Monte Vista High School by visitors of our site.
What percent of students have achieved state testing proficiency in math and reading?
13% of students have achieved math proficiency (compared to the 34% CA state average), while 27% of students have achieved reading proficiency (compared to the 47% CA state average).
What is the graduation rate of Mt. Diablo High School?
The graduation rate of Mt. Diablo High School is 78%, which is lower than the California state average of 87%.
How many students attend Mt. Diablo High School?
1,397 students attend Mt. Diablo High School.
What is the racial composition of the student body?
74% of Mt. Diablo High School students are Hispanic, 8% of students are Asian, 8% of students are Black, 5% of students are White, 4% of students are Two or more races, and 1% of students are Hawaiian.
What is the student-teacher ratio of Mt. Diablo High School?
Mt. Diablo High School has a student ration of 20:1, which is lower than the California state average of 21:1.
What grades does Mt. Diablo High School offer ?
Mt. Diablo High School offers enrollment in grades 9-12
What school district is Mt. Diablo High School part of?
Mt. Diablo High School is part of MT. Diablo Unified School District.
School Reviews
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