Biological Sciences Curriculum Study (BSCS) was established in 1958 in the U.S. Since the early time of BSCS, BSCS had developed high school biology programs and positioned evolution as the unifying theme in the center of those programs. There have been some previous studies on BSCS in Japan, but those studies have not focused on discussing the first BSCS programs and the teaching of evolution. The authors established two points of analysis as follows; 1) What aims and objectives did BSCS set up for the process of developing programs in early time, 2) What contents did BSCS introduce to the first BSCS programs and why has BSCS recognized evolution as a unifying theme in those programs. The authors have analyzed memorandums and minutes which were circulated among the steering committee members between 1959-63. As a result of our study, we have confirmed that since the establishment of BSCS one of the aims of BSCS was to develop scientific literacy on the part of high school students as future citizens and that BSCS emphasized evolution as the centerpiece of the unifying concepts of the programs, while also recognizing the importance of the nature of science as well as scientific knowledge.