You may well think that learning to read is a skill accomplished in primary school. And you are right, to an extent. But, with the amount of literature that an A level history student is faced with, if you read like you were taught to read at primary school you will either, a) be up all night working and rapidly begin to hate the subject, or b) have a nervous breakdown. It is the A level that involves the most reading, and the competent history student must learn how to read selectively.
So, here's a few tips:.
Don't read every word. You are often reading for a particular purpose. You might have been set a task to make notes on Jansenism in Seventeenth century Europe. You will not pick up Cowie's 'Seventeenth Century Europe' and embark upon reading it cover to cover. What you should do is check the contents, and then narrow down the search by looking in the index.
You may be looking for a certain topic, or issue. It would be worthwhile at this point jotting down a few questions about the topic, or a list of key words that you would like to know more about.
You still do not read every word. There are various methods you can use...
Skim the paragraphs, and read in detail the parts of the paragraphs that you find relate in detail to your topic.
Top and tail. Most paragraphs start and end with statements, and the middle parts explain the issue or provide evidence. If you have done a fair bit of reading on the issue, and you are really just after opinions, this is an excellent way to read. This can be used for whole articles, if you are not sure that you are going to gain anything new from (yet) another source.
Always start your reading with the easiest textbook that you can get your hands on, and gradually work your way up to the more complicated stuff. This way you will become more confident about the terms that are used and the main issues.
They are great, but only when used to highlight specific points. Some handouts that students are given by their teachers can look like colour-by-numbers when they are brought back to lessons!
Not doing the reading / reading the bare minimum. Your teacher will be able to tell.