He was also an executive committee member of the Central Conference of American Rabbis, and served as president of the Hebrew Union College Alumni Association from 1929 to 1931.
[3] Zielonka founded the Junior College, which later merged with the School of Mines, as well as the Associated Charities.
[3] Zielonka gave the baccalaureate sermon when David was ordained at Hebrew Union College in 1929.
[5] A large crowd of different religions and races attended his funeral at Temple Mount Sinai, including Bishop of El Paso Anthony Joseph Schuler.
Rabbi Edgar Magnin of Los Angeles prayed at the funeral and assistant rector of St. Clement's Episcopal Church Rev.