The use of time in school is undergoing close scrutiny. Over the years, educators have sought to enhance learning time through such reforms as block scheduling and year-round schools. School time can be conceived as an inverted pyramid, in which allocated time (total time in the school day or year) forms the top tier, engaged time (time-on-task)…

Arguments for lengthening the school day and/or school year are predicated on the notion that more time devoted to learning will yield proportionally higher achievement scores. Research reveals, however, that the correlation between time and achievement is far slighter than expected. The quality of instructional time is more important than…