This paper focuses on the study of the combination problems in the elementary school mathematics textbook, and studies from four aspects： arrangement distribution, material selection, content preparation and presentation mode. The results show that considering the stages in the development of students, decentralized arrangement and centralized arrangement combination; Rather than knowledge, background material mostly from individuals or groups of social life; In the variant reflects our textbook ＂step away＂ concept; Presentation more with pi...
