This may be due to the irregularity of their sleeping habits. According to a 2001 study, only 11% of college students have good sleep quality, and 73% have occasional sleep problems. About a quarter of students in this same study reported suffering from insomnia within the past 3 months, and over half reported feeling sleepy during the morning.

This is especially true for college students, since the deep sleep that occurs early in the night and the dream sleep that occurs later in the night are both required to learn. But the necessary amount of sleep varies from individual to individual. This is one case where quality is more important than quantity - if you feel alert and rested during the day, you've probably gotten enough sleep.

You can memorize facts during an all-night study session and recall the information through short-term memory for a test the next day, but you will most likely have to re-learn the material for a later cumulative exam.

An alert mind may make it difficult to sleep. Try to slow the pace of your activities in the evening. Do some light reading or watch TV until you become drowsy, and then try to fall asleep naturally. If there's a lot on your mind, try writing down a detailed list and then forgetting about it.

Avoid or limit caffeine and nicotine, which are stimulants, and alcohol, which can cause unrestful sleep and frequent awakenings during the night.

Twenty to 30 minutes of vigorous physical activity enhances deep sleep, but avoid exercising in the 6 hours before bedtime since it increases alertness.

Naps of less than 30 minutes can actually be quite refreshing during the naturally occurring mid-afternoon slump, but napping for much longer than this can make you drowsy and interfere with a good night's sleep.

Try to go to sleep and wake up at the same time every day. A regular sleep pattern reduces insomnia, and increases your alertness during the day. It is easier to get sleep each night when you have a more consistent bedtime. It can take up to four days to reestablish disrupted sleep patterns. It is also better for your body when you get up at about the same time every day. While you may sleep in a little on the weekends, it is best to avoid sleeping the day away as this will throw off your sleep pattern.

Changes in volume and light from the TV or other screen can be disturbing. If you like falling asleep to the TV, try to use the timer function. Or if you’re trying to watch something to tire you out, it is best to get out of bed so as to not associate the bed with sleeplessness.

Strive to eliminate as many light sources as possible, from both inside and outside. Consider investing in heavier blinds, blackout curtains, or an eye mask.

If you choose to work or study in bed, your mind may start to associate these activities with bed. Try to work or study elsewhere and leave the bed for sleeping (and sex) only.

Use earplugs, a white noise machine or app on your phone to block out exterior sounds. Add more sound-absorbing fabrics to your room with rugs. Talk to others in your room, suite or hall about establishing “quiet hours”.

It is best to allow a couple of hours to digest a full meal before bedtime. If you’re hungry at bedtime, a light snack helps to deal with a growling stomach without disrupting sleep with indigestion.

Try to wear loose clothing so binding fabrics do not wake you up. If you prefer to sleep with little or no clothing, make sure you have sufficient blankets to keep you warm so being cold does not wake you.

Most people sleep best in a cool, but not cold, room. When it is cold, rather than turning up the thermostat, consider adding another blanket.

Odors from food and crumbs in bed can disturb sleep. Try to keep food in the kitchen and dining areas of the house or residence hall.

Plants help create oxygen and diminish the carbon dioxide in the room, thus keeping the air fresher while you’re sleeping.

Falling asleep to the radio or music could cause sleep disruption later due to changes in volume.