In high school you have some subjects only in 1st or 2nd year that will be on your final "grade card" where you can be drafted for one or two exams, usually you have to do one. In the 3rd year you are drafted for 2 exams, 1 written and 1 oral. The exam grades from the 3rd year does not count towards your grade in those subjects, but get put on your "grade card" individually.

All grades are between 1-6 where 1 equals F. When all grades from all your HS-years are ready, you simply add them all together, then divide by number of grades, which gives you e.g 4.5. If you take science classes harder than the obligatory ones, you get extra "science points" (usually 1 per subject) added to your overall undivided score. The universities then look at all their applications, then calculate what score you need to get in. Usually this is done with the undivided score, and lets take the nurse school at University of Oslo as an example here, where you need 62 study points to get in.

That means you need 6/A in all subjects + 2 science points to get in, due to the amount of applicants. Much like Australia's system, but with different scoring.

In Italy university don't look at all at your high scholl career (only people who have great votes can have an economic help but nothing more)... everyone who finish high school can go to university. For some kind of study is needed a test (for example medicine).
Lot of kind of study have a closed number: for example I wanna do architetcture, but place available are only 100, first 100 can do that, others not.
That works for private and public university. There are payment rules that looks at the annual family income to establish how many money you've to pay every year.

that's one of points i was trying to get to. i get the feeling that many people go to uni just to say they're in uni and well...for parties. some of them don't seem to realize that the best thing for them was to try to get a job like you did. I'm not saying that this is your case as you are way more talented than most of the college students in your area i know, but it was your choice, and i totally understand that.

@ilPoli: we also have only a certain amount of available places. I study IT at FEUP (one of the best colleges in the country), which has about 100 places/year and has a entrance minimum average score rounding 16 out of 20. But obviously there are another institutions, for example private schools, with the same courses but WAY lower entrance score.

Thanks for the replies guys.