Using Lisp-based pseudocode to probe student understanding

We describe our use of Lisp to generate teaching aids for an Algo-rithms and Data Structures course taught as part of the undergrad-uate Computer Science curriculum. Specifically, we have made use of the ease of construction of domain-specific languages in Lisp to build an restricted language with programs capable of being pretty-printed as pseudocode, interpreted as abstract instructions, and treated as data in order to produce modified distractor versions. We examine student performance, report on student and educator reflection, and discuss practical aspects of delivering using this teaching tool