Sasaki's studies in California ended abruptly with the outbreak of World War II. After a brief time in an internment camp for Japanese Americans, he worked in the sugar beet fields of Colorado, and later in a photographer’s darkroom in Chicago. He received a B.F.A. in landscape architecture in 1946 from the University of Illinois, where he studied under Stanley White and Karl B. Lohmann, and in 1948 completed his M.L.A. at Harvard University.