It varies from parts of the country too You start primary school at 4 here

Not to mention it changes too often too. I only took my A-Levels 3 years ago, and the system was completely different to today's A-Levels - people would normally only do 3 (I've got 5), with an optional 4th of being General Studies A Level or a GNVQ (I chose GNVQ). But even this was subject to which part of the country you were in