I moved to Finland a couple of years ago and have two kids at school. The key differences I see (compared to Aus) are:
- later start (7 years old grade 1)
- hot lunches
- every kid gets the same education, almost no private schools, no advantage in going to a different school
- multiple languages are taught
- teaching is quite a prestigious and reasonably well paid occupation
- lots of small schools (they scale wide, not high, from a hardware perspective)
Of course these are basic observations, not a study. I have no idea how they get such good results, but they do.