Novices often find learning their first programming language to be a frustrating and difficult process. They have difficulties in developing and debugging their programs. One of their problems is that their mental model of how the computer works is inadequate.
In this paper we discuss a programming assistant, called Bradman, which we are currently developing. It is aimed at novice programmers and designed to reinforce a concrete mental model of how the computer works as a program is executed. It shows explicitly how program states change as statements in the imperative language C are executed. It does this by means of graphical display together with contextualised verbal explanations of each statement.
