Isaac Physics is a project designed to offer support and physics problem solving to teachers and students from Year 7 through to university.
The best way to improve your grade in your final exams is to practice as many questions as possible so you become confident with the underlying physics. It takes time but if you continue to practise you will master it!
There is a website that has thousands of questions for you to answer online. You can create a free account so you can record your progress (and even share this with your teachers).
It is a project run by the University of Cambridge and supported by the Ogden Trust with the aim of developing the problem solving ability of students from GCSE to A Level (and beyond).
Isaac Physics - Essential A Level Game Boards