Students' understanding of object-oriented (OO) program execution was studied by asking students to draw a picture of a program state at a specific moment. Students were given minimal instructions on what to include in their drawings in order to see what they considered to be central concepts and relationships in program execution. Three drawing…

When visualization tools utilized in computer programming education have been evaluated empirically, the results have remained controversial. To address this problem, we have developed a model of short-term effects of program animation, and used it in a series of experiments. In the current experiment, we varied visual representation of an…

Roles of variables is a new concept that captures tacit expert knowledge in a form that can be taught in introductory programming courses. A role describes some stereotypic use of variables, and only ten roles are needed to cover 99% of all variables in novice-level programs. This paper presents the results of an experiment where roles were…