St. Leo the Great School was originally begun by the Sisters of Notre Dame de Namur of Amiens, France and opened in 1915 with 90 students.

[3] The original school building is still used today as the preschool, gym, parish hall and kitchen.

In 1927 the Reverend Henry J. Lyne reopened the school with the support of the Sisters of Charity of the Blessed Virgin Mary.

[5] St. Leo students won the Bellarmine College Preparatory four-year scholarship in 1937 (Franklin Lawrence)[6] 1938 (Dick Wehner),[7] 1939 (Robert Wehner), 1940 (Louis Mattiesen), and 1940 (Walter E. Rankin, Jr; the third consecutive year a St. Leo student scored top marks on the exam).

In 1984 Principal Sister Dorita Clifford, BVM, was mentioned in the New York Times for her early adoption of computers at the school.

[9] In 1985, the Sisters of Charity of the Blessed Virgin Mary turned over school administration to the lay staff of the Diocese of San Jose's department of education.

[10] In 2007, a "Little Lions" preschool was added for three and four-year-olds, with a purpose-built addition to the front of the original school building with its own classroom, bathrooms and play yard.

The school offers several after-school programs: choir, drama, soccer, tennis, theater, Robotics, cheerleading and student council.

The graduating 8th grade class routinely collect more than 130 Thanksgiving Day birds that are donated to Sacred Heart Community Service.

Sock Hop - At the beginning of the school, the entire community gather for food, dancing, entertainment and games.