A tool constructed to examine a task’s potential to stimulate and support creative
mathematical thinking was derived from a hierarchy of cognitive activities students
employ as they solve unfamiliar problems. These cognitive activities informed the
formulation of categories of task features that support creative mathematical thinking. Use
of this tool is illustrated in a study of the mismatch between potential student responses to
a task and actual student responses to the task as implemented. The sufficiency of the tool
is discussed.