Where I live, school is divided.
ElementeryKindergarden-5 (about 5 to eleven years old)
Middle 6-8 (eleven to thirteen)
Highschool (13 or 14-18 or 19; if you take summerschool highschool can be completed in 3 years)
Collgege/University doesn't have age restrictions. My 50+ year old aunt went to college a few years ago.
Ric, in the US we go from mid august to mid december, then from early january until the end of may, a total of circa180 days.
And it isn't tests that I find most stressful. It seems some teachers don't want to belive kids have a life outside their classes, and they'll load you down with homework and expect you to have it done. Unless you have a disfiguring injury or something like that.
But the worst part is watching her grow more beautiful for three years and knowing I am nothing more than a high-school aquaintance to her, and fearing that that is all I'll ever be.