Castelar Elementary School (1882- ), originally named Castelar Street School, was founded in 1882 on the southwest corner of what is today College and Hill Street. When Castelar Street changed its name to Hill Street, Castelar Street School changed its name to Castelar Elementary School. At the time of its founding, the school building had four rooms and offered classes from first to eighth grade. It had four teachers and 300 students, of which one-third had Spanish surnames and two-thirds had Anglo surnames. When a fire destroyed the school in 1904, a new two-story wooden structure was built. The student body gradually grew to include the children of French, Serbian, Yugoslavian, Croatian, and Italian immigrants, as well as an influx of Chinese immigrants in 1923. As a result, the school added five new classrooms to accommodate the expanding student enrollment, most of whom were Asian or Latinx. The Immigration Act of 1965 brought immigrant children from Hong Kong to the school, and a large influx of immigrant children from Southeast Asia in 1975. By 1977, the school expanded to thirty-three rooms and by 1980, enrollment reached 1,156 students. Currently, Castelar School includes kindergarten through 7th grade, and holds a dual language program in Mandarin.

Dr. William "Bill" Chun-Hoon (1928 - 2019) was an educator in Chinatown, Los Angeles. Chun-Hoon was born in Honolulu, Hawaii. In 1973, he became the principal of Castelar Elementary School and the first Chinese American principal in the Los Angeles Unified School District. He created community programs, adult classes, and bilingual education in Chinese and Spanish to aid new East Asian and Southeast Asian immigrants following the Immigration Act of 1965 and the Vietnam War. As director of Friends of the Chinatown Library, Chun-Hoon advocated for the creation of the Los Angeles Public Library branch in Chinatown at Castelar Elementary School. Chun-Hoon further served on the California Community Colleges Board of Governors and supported the Chinese Historical Society of Southern California. In 2005, the Chinese American Museum awarded him the Lifetime Achievement Award.

Ella Yee Quan (1926-2014) was born in Santa Barbara, California in 1926. She initially worked as a nurse's aide and as a typist before entering the field of education in the late 1950s. She earned her Bachelor's and Master's degrees in Education as well as an Elementary and Adult Teaching Credential from California State University, Los Angeles. She also received a Secondary and an Administrative Credential from Mount St. Mary's College and a Bilingual Cross-Cultural Credential from the University of Southern California. From 1964 until her retirement in 1989, Quan worked as a teacher, assistant principal, and principal in several schools within the Los Angeles Unified School District, including Castelar Elementary School in Chinatown. She also developed bilingual teaching materials for non-English speaking students of Chinese, Japanese, Filipino, Korean, and Samoan descent. In addition to her illustrious educational career, Quan was involved in several community organizations, including the Chinese Drum and Bugle Corps, Chinese Language School, Services for Asian American Youth, and Asian American Educators Association. She was also a charter member of the Chinese Historical Society of Southern California, where she would serve as president. Quan passed away in 2014.