Persistent conceptual bugs exist in how novices, from primary school to college age, program and understand programs. These bugs are not specific to a given programming language but appear to be language-independent. The three different classes of bugs are: (1) parallelism, the assumption that different lines in a program can be active at the same…

Seven graduate students in a seminar on classroom computing received instruction in LOGO programming. Programming protocols were collected periodically and examined for errors and misconceptions; in-depth interviews were conducted in order to understand specific misconceptions better. As novice students transit from instruction to experience in…