Listening in class is a skill, which means you have to practice it. Just as you would have to practice basketball to be a better player, you also have to practice listening. How to listen in class?
One of the things you need to do is to make sure that your mind doesn't wander (神游). It's easy to start thinking about other things, especially when you 're not interested in the subject. So make yourself pay attention to what the teacher is saying.
Next, listen to the main ideas. If you want to catch every little piece of information, you'll be exhausted (疲惫的). It's too much work and it's impossible to do. You'll also need to look at the teacher. Not only does this show respect to the teacher, but it also helps prevent your mind from wandering. There are too many distractions (使人分心的事) when you have class. It might be a friend who is trying to pass you a note. Or it could just be someone talking to his deskmate; it can even be some birds outside the classroom windows, or a group of kids who are talking loudly as they pass by the door of your classroom.
Finally, you need to take notes because you will not remember everything the teacher says in class. So you have to have a notebook to write down key points so that you can study them after class. Taking notes also makes you focus on listening. Listening isn't always easy, but if you follow these simple steps, you'll be much more successful in your classes.