Mastery achievement of intellectual skills

In an investigation of the improvement of mastery learning techniques through instruction based on a validated learning hierarchy, it was found that it was highly effective to present tasks in a sequence consistent with the requirements of the hierarchy, and to require learners to demonstrate clearly their achievement of each task in turn before being allowed to proceed to the next. With this technique, nearly all of a group of relatively young students were able, to perform the skill better than a group of students three grades higher who had been taught the skill as part of their normal lessons.