How To Pay Attention - It Can Be Done
Start by finding a seat as near to the front of the class as possible, preferably in the first few rows. Being up front puts you closer to the teacher or professor and gets you more on their radar. Being up front makes them more aware of you and should help you to be attentive while in class.
If being in the front of room is something you are not fond of, try to find someone in the class that interests you and take a seat next to them. You could try to engage them in a conversation or ask them questions if something does not make sense to you.
Make eye contact with the teacher. Making eye contact with the teacher will force you to focus on the teacher as they walk around the room and go back and forth to the blackboard. While making eye contact, nod when you understand what is being said and make faces when you do not understand. This will let the teacher know you are paying attention.
Ask questions in class or participate in the class discussion. Doing these will help you to pay attention because to be involved and not sound foolish, you need to know what is being taught in the class and to be aware of what has been taking place in the class.
All during the class take notes. To take notes, you will need to be alert with the class so you know what is going on and what the important points are that need to be written down. Keep your hands and mind busy and that will make the class go by faster.
There will always be situations where you do not want to be there and it is very difficult to concentrate. By doing a few key items, you will be able to keep your mind where it is supposed to be and not wandering off.