Software Visualization As A Pedagogical Tool: Redressing Some ITS Fallacies

: The long-term future of Intelligent Tutoring Systems (ITSs) for the teaching of programming is severely hampered by weaknesses which prevent ITSs from scaling up to cater for either a wide audience or a broad curriculum. The weaknesses include an emphasis on toy examples, the use of instruction-based (as opposed to guided discovery-based) teaching, a lack of attention to user interfaces, and the belief that it is possible to create a comprehensive bug catalogue. We propose an alternative approach, based on examining the needs of expert programmers, and considering a pedagogical trajectory which caters for development from novice to expert. The common thread through this trajectory is "Software Visualization", a collection of techniques which allows beginners to see the innards of program execution clearly, and at the same time allows experts to view high level program abstractions which help them home in quickly on buggy code. We re-work some well known examples from the ITS communit..