This question type uses a computer algebra system to evaluate student responses constructed as mathematical expressions. The ability to provide a range of feedback based on different incorrect answer pathways make this option very useful for formative assessment.

This question type has been released after a pilot phase where the Department of Math and Stats trialled the functionality on a separate server.

Anyone interested in detailed information about creating and using STACK questions should contact the pilot lead, George Peschke and should also consult the detailed in-system documentation.

Note that due to the STACK question performance issues identified in July 2022, instructors using this question type should be ensure that any self-authored questions conform to the guidelines for future-proofing questions (this does not apply to any questions being shared from the central Department of Math/Faculty of Engineering shared question repository as these have all already been edited). Specifically, instructors should take note that all functions and variable statements must be terminated by semi-colons in order to avoid time-out errors due to long background computations.

Instructors should also make sure that they create and deploy random variable variants matching or exceeding the number of students taking the exam. Variants can be deployed (or viewed) by clicking No variants of this question have been deployed from within the question editing screen: 

Then entering a number higher than the number of students and clicking Go: