Mathematics educators using
problem solving for evaluation have an issue phrased by
Alan H. Schoenfeld: :How can one compare test scores from year to year, when very different problems are used? (If similar problems are used year after year, teachers and students will learn what they are, students will practice them: problems become
exercises, and the test no longer assesses problem solving). The same issue was faced by
Sylvestre Lacroix almost two centuries earlier: :... it is necessary to vary the questions that students might communicate with each other. Though they may fail the exam, they might pass later. Thus distribution of questions, the variety of topics, or the answers, risks losing the opportunity to compare, with precision, the candidates one-to-another. Such degradation of problems into exercises is characteristic of mathematics in history. For example, describing the preparations for the
Cambridge Mathematical Tripos in the 19th century, Andrew Warwick wrote: :... many families of the then standard problems had originally taxed the abilities of the greatest mathematicians of the 18th century. ==See also==