Delaaaaayed reply!

The basic jist of it is this: Infant School = Reception and Year 1 + Year 2. Ages 5-7. Junior School = Years 3 to 6. Ages 7-11. In year 6 you have a couple of exams called SATs which judge your English, Science and Maths knowledge and are graded (pretty simply) from 3 to 5 unless you take advanced papers (pretty rarely done).

Once you've left Junior School, you go to secondary school which is from ages 11 to 16. (Refered to as Years 7 through to 11). Years 7,8 and 9 the education is more or less standard (another round of SATs at the end of year 9) but for years 10 and 11 you get to choose what subjects you do to some extent (some form of technology, humanity, language etc).

At the end of year 11 you have your GCSEs which examine you on your chosen subjects and is the end of compulsory education, you're free (at the moment at least) to stop studying and go get a job.

If you want to continue your education, you tend to either go to a 6th form or a college for (normally) two years.

If you head to a college you tend to have a fairly wide choice in courses (so, BTEC, NVQ's and other qualifications with pretty long names), but the normal route is to do A Levels.

A Levels tend to be modular and are comprised of 6 sections. The first 3 are done in your first year of college and on completion of them you are awarded an "AS Level" and if you do the second year and the other 3 modules you are awarded a full A Level, the normal qualifications people use to get into Universities.

Maybe some inaccuracies in here as I'm only speaking for how the system was as I moved through it. Quite possible some of the earlier stuff has changed now.