Abstract
The concept of the complement is widely applied in the calculator, mental arithmetic, abacus calculation, and etc. The 10's complement game may also be helpful when children was calculating and developing their number concepts of “embedded number”. This study aims to guide students to realize the concept of 10's complement by the game interface of graphic thinking, and survey the process of observation in order to review observing underachievement students' playing by the qualitative study. The results of study present the influences on the game interface for graphic thinking of operational process to underachievement students in mathematics addition games, and can be used as future reference for math addition game design.