Young kids are often morning people, but teenagers biologically have something going on that makes them almost universally not morning people. Forcing teenagers to go to school in the dark for several months of the year can make it very difficult for them to get to school, and leave them half asleep during school. This will have an impact on their grades, which can have a follow-on impact on their whole life.

We should probably start high school later in the morning even if we stay on standard time ; it's way more important if we switch to permanent daylight time.