Tbf it’s not gonna fix anything, teens need a LOT of sleep and their rhythm stray to as far as 4-5AM, so even when starting at 9 they won’t get a lot of sleep

What in my opinion would work is reducing school times a bit and have morning and evening batches with different staffs and the student could choose which time they want to attend, the productivity would be much higher making the lower time period not a problem, tho i am pretty sure there might be some issues in this system remembers CGP grey’s rule