If you’ve ever swum in a hotel swimming pool, you’ve likely seen
the sign: “No diving! Water depth is too shallow.” The pool is
not deep enough to allow safe diving, and the fear, of course,
is that the hotel will be sued if swimmers injure themselves by
diving head-first into the pool. It is probably a good policy
for hotels, but not for constructing lasting learning. According
to memory researchers, depth of processing increases retention.
Why? Because deep processing “allows a richer and more elaborate
code, which in turn becomes more readily available.”1 This idea
is not a new one. In 1890, William James wrote: “The one who
thinks over his experiences most, and weaves them into
systematic relations with each other will be the one with the
best memory.”2 The message: to make learning memorable, engage
students in deep thinking about new material. But what
constitutes deep thinking in new learning? Research suggests two
mental activities, comprehension and elaboration. Comprehension
involves organizing new