In the Google Sheet of renaming recommendations, they put a Wikipedia link to José Bernardo Sánchez, a Spanish missionary who in 1806 accompanied a military expedition against the Californian indigenous peoples.
Sanchez Elementary School was named for Sanchez Street in San Francisco, which in turn was named after Francisco Sanchez. Francisco Sanchez was Mexican, born in San Jose when California was still part of Mexico. He died in 1846 and is buried at Mission Dolores near the school in San Francisco.
SFUSD reports the student body at Sanchez Elementary is 81% Hispanic with many students whose primary language is Spanish. Sanchez is one of the few schools in SF with a name tied to Mexican heritage.