Hello,
We are new to the British school system (German/French family) and have a four year old who is due to start Reception in September.
As we only recently moved back to London from abroad, we are late in the process, and I am desperately trying to get my head around the very complex system here.
Firstly: I think I am pretty certain to want to avoid the 7+ exams as it seems like a lot of pressure to put such a small person under. So that would rule out any pre-preps that only go until 7/8. But are there any advantages to sending your child to such a school? It seems like some of the top prep schools (that feed into the top secondary schools) only accept kids from 7/8.
Secondly, we have narrowed our choice down to a handful of schools (choice is limited of course at this point) but they all end at 11+. Now I heard that girls tend to leave for secondary school at 11+, and boys mostly leave at 13+. Why is that?? And also, what happens to all the boys in schools that stop at 11+? Are they automatically excluded from those top schools that accept kids from 13?
Is it fair to say that one route is pre-prep (7+ exams), prep (13+) exams, and then secondary school. And the other route to chose is prep from 4-11+, and then secondary school at 11?
Or are there preps that cater for children from 4-13?
I honestly have no idea how our son will develop in school and it’s not like I have my heart particularly set on the likes of Eton or Harrow. I just would like to not exclude that option by default because he left primary school at 11.... it seems like here one literally has to think 15 years ahead and it’s stressing me out. 
Could someone enlighten me on the pros and cons of the different routes, what options there are, and which questions I should be asking myself at this point? Every time I feel like I found my answer and made a decision, some new piece of information pops up that gets me all confused again.
For info, we are looking at Co-ed schools in South and South West London.
Thanks in advance!