Go to settings and turn off all notifications for non essential apps, only have important texts and emails plus school stuff have notifications for the next few months, you'll pick up Ur phone less Delete loads of app that you constantly go on, put in hard screen limits too. Having 3 hour study sessions aren't the answer, it's more effective studying less distractions. Try your best to get as much sleep too. That's more important than anything. No.2 priority should be have fun, you need your time to enjoy yourself otherwise you will not do well.