Recently we learned that schools in Finland rank towards the top of the heap in all sorts of subjects. The rest of the school systems, quite frankly have a school days crush on the nation that can do so much with so little.
The Smithsonian magazine recently went to the Nordic nation to find out. They also learned that the school system isn't as homogenous as one might assume, and, in fact has a surprising number of immigrant children.
I'd recommend first reading a summary of the Smithsonian report at National Center for Policy Analysis which puts the points into a list, missing little of the main points of the original piece. I believe though they don't directly say that Finland makes sure that teachers are plentiful and are given a lot of help by copious community hiring so that they end up with a teacher or an aide available for every seven students.
Teachers have more education (which is paid for by the government) and are given much respect (comparable to doctors and lawyers) and are offered extra training free, but are not hamstrung with mandatory standardized tests or one method fits all teaching practices.
See NCPA's Summary: Why Are Finland's Schools Successful?
Or See Original Smithsonian report: Why Are Finland's Schools Successful?