1. THE GOAL
Find out WHAT you should learn (what you should know before, for example, the test) even before you start something new in school. write down your goals!
Prepare the brain by hanging out small hooks of knowledge in the brain - find out a fact in advance about what you are going to work with in school.
3. FOCUS STEWERS
Make sure you can work undisturbed, that nothing (such as your mobile phone, siblings, noise or anything else) steals your focus from school assignments. The same goes for school.