Late start benefits HS students

From Poynter.org:

The National Sleep Foundation has been saying for some time that it makes a lot of sense to start high school classes later in the morning -- not at 7 a.m., as is the case in many school districts nationwide. Now, some school districts are beginning to respond, and they are seeing good results. Some districts are even saving money by cutting bus runs.

See it wasn't just me who was tired every morning. Apparently all high schoolers do better when they get to sleep in every morning. I say run the school day from 9 to 5. Any thoughts?