Body temperature is often highest in late afternoon and lowest in the morning.
Here is a little test to see what your optimum body temperature and time of day for studying are. Save six crossword puzzles from newspapers or buy a puzzle book. Repeat this same process for the next two days, remembering to chart the time, your temperature, and the amount of each puzzle you are able to complete in ten minutes. By looking at your chart, you should be able to see the body temperature and time of day at which you function best. After you see when you are at peak performance, you will know when you should schedule study time, or especially when you should study for your most challenging courses.