Hello I think he has dyslexia It's better to consult local psychologist

If you are sure there is no problem with his vision, he may have a learning disability or dyslexia. Get an opinion of an Ophthalmologist anyways. If everything is fine with the eyes then meet a child psychologist. It is best to start treatment as early as possible.

Hello there I can understand your concern Sometimes despite having normal vision the child is unable to follow what is written on the board for a simple reason that he is sitting a little too far away from the board or his view is obstructed by something or someone and at this age when a child is thinking of something else he could miss things on the board . You just have to train him and speak to him . Best regards Dr. Anil kumar jain