In an article written many years ago, I wrote, "a teacher teaches in the same sense that a cook cooks." My point was that a cook does not really cook; it is the meal that cooks. What a cook does is to fix the food so that it will cook. Similarly, a teacher does not really teach; a teacher fixes conditions that enable a student to learn. However, there is an important difference between a cook and a teacher: A meal has no alternative but to cook the way it was prepared by the cook, but a teacher cannot force a student to learn. The best teacher in the world cannot put knowledge into a student's mind. The only person with access to your mind is you.
Active participation by the learner is therefore necessary for verbal learning. This is because practical, useful world knowledge is not verbal. We use words to depict objects and events, to describe experiences, and to express ideas. The fact that we can usually express the same idea in different words is conclusive evidence that the idea is distinct from the words. Some word may express the idea better than other words, and searching for just the right word further indicates that the idea comes before the word. Accordingly, verbal learning is not really learning words. . .it is learning from words.
Because you are the only one who can translate knowledge into our memory system, you have to pay attention in order to learn from words. Occasionally, a teacher's voice will be so powerful that you listen whether you want to or not (that is why TV ads are louder than the program), but as a rule you have to sustain attention voluntarily on the words in a lecture or a textbook. The most critical difference between the good and the poor student is not intelligence, it is the ability to maintain attention on the material to be learned.
The good news is that paying attention is a learnable skill. One aspect of the skill is learning to discern when your attention is starting to wander. Keeping a diary of lapses can help. Another aspect of the attention skill is knowing what it feels like really to be paying attention. Practice listening to soft sounds or reading with distractions. Recall also that competing needs make your mind more distractable. Finally, give your mind a break from time to time.