Studies in cognitive science have verified that working memory (where the brain solves problems) can manipulate nearly all elements of knowledge that can be recalled automatically from long-term memory, but only a few elements that have not previously been well memorized. Research in reading comprehension has found that "lecture notes with clicker questions" can move a portion of lecture content to homework. By applying these findings to the design of homework-tutorials for students, under the right conditions, we found that time for active learning during lecture increased and student achievement measurably improved. Factors that have affected the outcome of our experiments are discussed. This communication summarizes one of the invited papers to the ConfChem online conference Flipped Classroom, held from May 9 to June 12, 2014 and hosted by the ACS DivCHED Committee on Computers in Chemical Education (CCCE).