Dear Jim
I am sorry to hear that you are ill and can't go to school.I hear you have a fever.Don't be too sorrow about that.You'd better go to see the doctor.You should take some medicine and drink lots of hot warter.You'd better eat fresh vegetables and fruit because they are good for your health.Don't worry about your study.I will come to see you and help you with your homework after school.
Hope you can get better soon