For example, in the third grad, when fraction were introduced, the problem presented was about measuring a student's arm. The text highlighted the need to express fractional parts (Fig.3). The text then presented a hint to direct students to a solution to the problem, followed by a summary of the new concept. The lesson was followed by a set of exercises for practicing the new idea or skill. There was little variation from this sequence, other than some lessons that omitted the hint or the summary.