Here's my suggestion and what I do
-get an early night's rest the day before and wake up early enough to do everything you've wanted to do in the morning.
-Don't fall into negative patterns, if you feel bad, go talk to someone, don't allow yourself to be by yourself, and if possible make sure it's girls
-Dull your negative inner voice, think of all the positive things you've accomplished to boost your brain.
- When you have some free time by yourself, after school, just chill by yourself for about a day or two so you can get lost in your thoughts and find out what's holding you back.
-I know this sounds hard, but you gotta realise it is just a game. Once you get that in your head, that tommorow's a new day and nothing here will last forever, then you can get back to your full potential. When i get into a rut (like I currently am) it is normally because I am overanalyzing little things, and not acting but reacting.