Bubble Sort is simple. Yet, it seems a bit difficult for high school
students. This paper presents a pedagogical methodology: Using Design Sketch to
visualize the concepts in Bubble Sort, and to evaluate how this approach
assists students to understand the pseudo code of Bubble Sort. An experiment is
conducted in Wu-Ling Senior High School with 250 students taking part. The
statistical analysis of experimental results shows that, for relatively high
abstraction concepts, such as iteration number, Design Sketch helps
significantly.