OMG! reading all this is so weird!
In New Zealand...we start 'primary school' at 5, that's for 8 years... then it's on to 'intermediate school' for 2 years and then to high school for 4/5 years. I'm 16 and just about ready to start my last year of school *can't wait*
Our school year goes from end of Jan (Jan 27th we start this year) and goes in 10 week slots with 2 weeks in between every 10, if you get what I mean...so by the time our summer break comes around it's usually early november to mid december depending on whether you are a senior and have end of year exams or whether you're just a plain ol' junior
We also have MUCH different course choices, last year I took Math, English, Home Economics (cooking), Geography, Music and Science (last year Math, English and Science we compulsory) and this year I'm taking Math, English, Catering and hospitality, Music, Child care and Computer applications. (only English is compulsory this year)
so...I could go on to do another year of school ('7th form') but I decided not to, many people don't do it because it's just a year to get all your stuff for Uni...and if you don't want to go to Uni because you have other plans or other education things (courses etc.) planned out then 7th form is just a waste of a year.
Even if you go to 6th or 7th form (legally you can drop out as soon as you turn 16) we still don't have a graduation ceremony. All it is is you get your exam results back after christmas and that's that. If you want to get together a group of friends and go out and party then that's your choice but...otherwise, no fancy graduation things here. But for 5th, 6th and 7th form (at my school) you get to go to the 'ball' (dance) if you like....