You should be thinking about your subjects not simply in lessons, but also between lessons.
The formal work set by teachers represents the minimum requirement, and you should always review your current work in Study periods. You should also quickly get into the habit of reading widely and engaging in investigative research. You should make notes on everything you read and thus learn how to summarise the most important features of a textbook chapter or article.
Teachers are but one of a number of sources of information, and you are advised to recognise this from the outset. They will, of course, suggest suitable reference material and resources, but it is your responsibility to consult it and make full use of it. You will quickly discover that textbooks are a useful aid but a dangerous master; the unthinking copying of sections of textbooks, or pasting form the Internet, as a means of ‘getting homework out of the way’ is easily identified and utterly worthless. You should be sufficiently interested by your A Level subjects, and this requires a personal involvement. The passionless recycling of textbooks or website pages and bland processing of class notes simply advertises a lack of any such involvement.
The excitement of personal and academic development is linked to intellectual curiosity and an energetic commitment to independent reading and thinking, both within and beyond the specification and classroom. You must learn to develop judgement in selecting and evaluating your material; concepts and techniques must be mastered, and then applied, and to carry out these important tasks, it is essential that everything you read and write is thoroughly understood. When your written work is returned, you should always correct errors, and add material and ideas that you omitted. Work is not completed when it is handed back; the accompanying comments are far more important than the mark awarded, and the learning process incorporates your corrections and additions. Keep a sensible balance between your subjects, and don’t make the common error of simply ‘marking time’ in one of them for a term, for this will cause problems to mount up at a later date.