introduction

Not all students who are always stay up at night, will pass their examination with flying colours. Why does it happen?In a 1998 survey of more than 3,000 high-school students, for example, psychologist Amy R.Wolfson, PhD, of the College of the Holy Cross, and Mary A.Carskadon, Phd, of Brown University medical School, found that students who reported that they getting C's, D's, and F's in school obtained about 25 minutes less sleep and went to bed about 40 minutes later than students who reported they were getting A's and B's