If you guys are having touble in school , try working in a different enviroment . Im guessing you guys tend to study and work in your room , wich is fine but it could be the reason for the lack of consentration. So if you do use your room as your "study room" , there are a few things I recomend to make your enviroment more relaxing and non-distracting.
1. Have a clean enviroment - the less the mess , the better the test and its easy on the eyes.
2. Remove or hide any possible electronics that could cause distraction or temptation.
3. Listen to some soft or classical music as background noise .
4. Get a house plant - Seriously , there cheap , easy to tend to and gives you a sense of acomplishment and its very rewarding.
5. Make personal time for yourself - Everyone needs a break while working so why not set a time in between to do somthing that you want to do. Im not talking about playing the ps3 or hopping on toribash , more so what you actualy enjoy doing ( drawing , painting , reading).
Now the most improtant thing is eating heathly , especialy for breakfast. Eggs are the best way to start the day , pumps you up full of energy so you can focus better during a lecture.