The Australian school system is divided into three levels of school, for each age group:

-from 4 to 6: pre school

-from 6 to 12: primary school

-from 12 to 18: secondary school

-over 18: university

Pre (preparatory) school is divided into two levels: creche and kindergarten.
Creche is for 4 years old children and it's basically a place where kids play and socialise, while kindergarten is for 5 years old children and it's pretty much the same as creche, with the only difference that kids start learning to write and read. In both creche and kindergarten there are 5 hours of lessons per day and lessons start at 10:00 am.

The primary school lasts for 6 years.
The first year is called "preparatory year" because it's a sort of a "bridge" between pre and primary school. Kids don't usually work much during the preparatory year, they socialise and play instead. The "true" primary school starts in the second year, although it is very easy, as the rest of primary school: the sixth year isn't difficult at all. During the 4th year kids can start German as elective subject.
"Electives" are subjects that can be chosen by the students, while "Compulsives" are the obligatory subjects. In the primary school classes change every year, so it's very difficult to have the same school mates as before in each year.

After primary school the secondary school starts, which is also called college The first two years, 7 and 8, are the "introduction years", and they're usually a big jump in difficulty for the kids: subjects are more and harder, and you often have to make new friends. Students can also choose the second language they'll study for the rest of high school, among Italian, French, Chinese and German. During the 9th and 10th year students can choose among six electives, for instance science and one language, and they have five compulsives, which are called "core". The last two years, 11 and 12, are usually full of exams and tests and students can choose among 12 electives: 5 for the first half of the year, 7 for the second half, where they can choose among 3 types of maths, philosophy, psychology, history, arts and music. They can even choose not to do either maths or English anymore: this way students can study one of them better. If someone fails in some subjects he can choose to either repeat the year or study during the holidays, which is usually very hard.

When high school finishes, students move to campus, where they get esaminated in every subject and start university. The length of university depends on what course they choose. Instead of moving to university, students can choose to leave high school after the 10th year.

In both primary and secondary the year is divided into two semesters and there are 6 hours of lesson per day, while students don't go to school on Saturday. There are 3 breaks during the day: the morning tea (11:00 am), which lasts 15 minutes, the lunch (12:45 am) which lasts 45 minutes and the afternoon tea, yet 15 minutes.
Lessons start at 9:00 am and finish at 3:15 pm. As for the holidays, Australian students have 6 weeks off school for Christmas, 2 weeks for Easter and 10 days 2 weeks after Easter.

In Australia there are public and private schools. The major differences are in costs and quality of education: private schools cost from 5000 to 40000 pounds and the quality of education is slightly better than the public's; also, private schools have better structures, and they often belong to religious institutions.