Learning environment in the traditional condition The traditional condition included
use of a computer-based learning environment that was developed and produced by the same
company that published the textbook and exercise book described above. The software was
meant as additional practice material (although the participating school did not use this software in the regular curriculum). The software offered a brief summary and a series of exercises
for each chapter of the textbook and exercise book, mainly calculation exercises, but also some
insight questions (measured by means of multiple-choice items). After completion of each
exercise, students received feedback about the correctness of their response as well as an explanation of the correct answer. At the end of each chapter, the system informed the student
about the percentage of correct responses for that chapter.