The Stanford psychologist Dr. Lewis Terman, famous for helping construct the IQ test, dedicated his research career to the betterment of children’s education. Starting in the 1920s, Terman charted all manner of factors that promoted a child’s intellectual success. One such factor he discovered was sufficient sleep. Published in his seminal papers and book Genetic Studies of Genius, Terman found that no matter what the age, the longer a child slept, the more intellectually gifted they were. He further found that sleep time was most strongly connected to a reasonable (i.e., a later) school start time: one that was in harmony with the innate biological rhythms of these young, still-maturing brains.
— Why We Sleep: Unlocking the Power of Sleep and Dreams (Matthew Walker), Loc. 4986–91