Ontario High School Home

About Us

The Chaffey Joint Union High School District serves the communities of Ontario, Montclair, Rancho Cucamonga, and portions of Fontana, Upland, Chino, and Mount Baldy. With over 25,000 students, the District is the fourth largest high school district in California. It has eight comprehensive high schools, a continuation high school, an online high school, a community day school, an adult school, and alternative programs. The District offers a wide variety of instructional options that provide a quality education for each student, every day. The District's well-prepared, dedicated, and highly qualified teachers and support personnel are second to none.
 
The Chaffey Joint Union High School District Board of Trustees are steadfast in the belief that "Nothing is more important than student learning and their achievement."
 
Our daily purpose encompasses our commitment:
"To provide student learning, and ultimately their achievement, of the prescribed curriculum that takes place in the classroom under the direction of the teacher." The Chaffey District supports this daily act. We realize that our efforts uniquely influence the future of our community and of this nation, and we are passionate about doing whatever it takes to prepare students to be successful and contributing citizens of the 21st century.
 
The Chaffey District has provided a quality education for high school students in the area since 1911. As the District continues to grow and progress, we are poised to meet the challenge of providing the finest quality education possible for every student. 
About Us Image
All CJUHSD students will graduate ready for college and careers.

Recent News

Finals Schedule

Please see the attachment inside for our upcoming finals schedule.

Upcoming Events

Board Meeting

Time: 5 PM – 8 PM
Location: Montclair High School

School Facts

  • 56% of Ontario High School graduates meet the University of California and California State University A-G admissions requirements, making it a leader in San Bernardino County.
  • 85% of freshmen at Ontario High School complete their first year of high school on track to graduate.
  • The CJUHSD has been named a Top Workplace by the Press-Enterprise and Inland News Group.
  • 522 Advanced Placement exams are administered to students at Ontario High School annually.

Principal's Message

Portrait of Larry Rook
Dear Jaguar Family,
 
Welcome to the 2025–2026 school year! It is with great excitement and pride that I welcome all of you students, families, and staff back to Ontario High School. Whether you are returning for another year or stepping onto campus for the very first time, especially our incoming Class of 2029, we are honored to have you as part of our amazing Jaguar community.
 
We understand that many of our students will be experiencing Ontario High for the first time, and we are committed to making your transition smooth, supportive, and memorable. Our beautiful campus will be buzzing with energy as our incredible student leaders from Band, ASB, Cheer, Dance, Link Crew, and more are ready to greet you and help you feel at home as we kick off what promises to be another fantastic school year.
 
You will be receiving your summer registration mailer via U.S. Postal Service shortly after July 7th. Please take the time to thoroughly review all enclosed materials. It is essential that all required forms in the registration packet are completed and ready to be submitted during our Summer Spirit Days.
 
Spirit Days (Schedule Pickup) We will be hosting our annual Spirit Days to distribute class schedules and complete registration tasks. Please refer to the schedule below to see when your class is scheduled:
 
Tuesday, July 29th
 
Class of 2028 (Sophomores): 8:00 a.m. – 10:00 a.m.
Class of 2027 (Juniors): 10:00 a.m. – 12:00 p.m.
Class of 2026 (Seniors): 1:00 p.m. – 3:00 p.m.
 
Wednesday, July 30th – Freshman Orientation
Students with last names A–L: 8:00 a.m. – 11:00 a.m.
Students with last names M–Z: 12:00 p.m. – 3:00 p.m.
 
These days are a great opportunity to connect with our staff, gather important resources, and get excited for the year ahead.
 
Parents and guardians, your partnership plays a critical role in your student’s growth and success. I strongly encourage you to get involved in the life of the school. Whether it’s participating in ELAC, School Site Council, Coffee with the Principal, or joining one of our many parent education classes, your involvement creates a meaningful connection between school and home.
 
If you are interested in joining any of our parent groups or learning more about how to get involved, please contact Ms. Jennifer McNatt, Assistant Principal of Student Achievement.
 
Together, we will continue to create a supportive and empowering environment where every Jaguar can thrive. I am excited and honored to lead this incredible community into a new year filled with learning, leadership, and legacy.
 
Let’s make 2025–2026 a year of excellence, pride, and Jaguar spirit.  Go Jags!
 
Larry Rook
Principal
Ontario High School