Founded in 1882, Castelar Street Elementary School originally consisted of a four-room building in which four teachers (including the principal) taught 300 to 400 children. As the second-oldest school in the Los Angeles Unified School District, Castelar has undergone several transformations. After the original schoolhouse burned down, the school expanded into two different structures, one built in 1904 (which was damaged beyond repair in the 1971 Sylmar earthquake) and the other in 1923. To meet the demands of this growing and diversifying community, the school was substantially expanded in the 1970s, including a large addition by Eugene Kinn Choy. Castelar was the first school in the district to hire staff that could teach in English, Spanish, and Cantonese.