Hi!
Well, I can tell you about the spanish school system.
First of all, we have a "pre-primary school" (I don't know how to name it, but here, we call it "Preescolar") where children from 3 to 5 years go and start learning the main things like the colours, and numbers...etc. Later, starts primary school, from 6 years old to 13-14 years old. After this, you should do "E.S.O" (in spain it means "educación secundaria obligatoria" and translating: "second education obligated") where teenagers stay there for four years. After that you can choose about three things: start working, doing "F.P" (which means Professional Formation and takes from 2 to 4 years, deppendig the course and after this you can go to university), or studying "Bachiller" which is like a High Grade, where you can get specific things that will prepare you to enter to university: so students choose what do they want to study in university, and they prepare only subjects for their careers. This "High Grade" takes only two years, and after that you can start university with a minimum age of 18 years old.
The information it's a little dissapointing maybe, but if you have any questions, or if you want me to explain you more things and details, of course you can ask me.
Hope I have helped you al little :)