Oak Hills High
Oak Park Elementary
Oak Ridge Elementary
Oak View Education Center
Oaks Middle
Oasis Elementary
Odell Young Alternative School
Oehl Elementary
Oleander Elementary
Onaga Elementary
Ontario Christian Academy
Ontario Christian Schools
Ontario High
Ontario Progressive Montessori School
Orangewood High (continuation)
Oro Grande Elementary
Our Lady Of Lourdes School
Our Lady Of The Assumption
Our Lady Of The Desert
Oxford Preparatory