There are two kinds of listeners - those who are passive and those who are active.
Passive listeners do more hearing than listening.
They are aware that the instructor is speaking, but they aren't making sense of what he or she says. Passive listeners may expect instructors to motivate them and to interest them in the topic. To get more out of lectures, become an active listener. Decide to listen. Deciding to remember is the first step toward increasing your memory's power.