A tool that you have to control sleep is an internal clock. This clock can be train so that it is easy to wake up and you feel less tired. When it starts to get dark outside this clock tells your brain to make a melatonin. This is a hormone that causes you to get sleepy. The light given off by screens confuses your brain and it stops making melatonin. As you get older your internal clock shifts making you want to go to bed and wake up later. A way to train your internal clock is to try and wake up at the same time everyday. This is easy to follow on school days but on days off try wake up within 2-4 hours of this time. You could also try to go to bed earlier if you need to catch up on sleep.