Why isn't there a simple study on how delaying school starts improve scores using existing data? Literally today, most schools start at the exact same "time" (

Why isn't there a simple study on how delaying school starts improve scores using existing data? Literally today, most schools start at the exact same "time" (8:00am). But there's a big shift in actual solar time if you're on the far east or far west of a given time zone: https://i.dailymail.co.uk/i/pix/2014/03/03/article-2572317-1C01C1CD00000578-141_964x612.jpg https://i.dailymail.co.uk/i/pix/2014/03/03/article-2572317-1... Do we see across the US a huge SAT score difference between kids on the most east of Pacific time and kids on west of Central time, and between kids east of Central time and west of Eastern time? And within a the states that are pretty uniform (not the costal ones, as the socioeconomic differences would probably be too big), is there a big difference of SAT scores between the eastern-most highschoolers and Western-most highschoolers?