I know how you feel I'm have mild insomnia and don''t usually get to sleep until around 3-5 Am and I get up at 7 Am and am always tired the next day. I sleep in every class from the beginning of the bell to the end unless theres a test or quiz. Last semester I had a 12.3% in english because I slept straight through and completed one assignment which I got a 98 on. If I wasn't so sleepy I would get A's and B's for sure. I still have a 3.0 GPA because last year I had to stand up all day.
He's just doinfg what he thinks is best. Just toke up before school and then toke up right after. If your lucky the high will last like 2 or 3 hours and you'll be good for the next 4 it works for me.