Lithuanian is not a Finno-Ugric language, but a Baltic one. Perhaps you are thinking of Estonian?
Personally I think using the metric system is more important for learning science than the instruction language. When you get down to it, the "simple Finnish words" are just as alien to everyday life as the Latino-Greek words. A word like "jännite" does not confer any more insight than "voltage". In advanced topics Finnish also uses loan words for things like electrons, momentum, grammatical cases and so on.
Whee, Finland is at the top of an international ranking. How groovy! It makes my white-and-blue heart beat with pride.
Except it doesn't, really. The purpose of a school, any school, in any country, is to prepare the students for the road ahead. "We do not learn for the school, but for life."
So while it is fascinating to study the performance of teenagers in a small selection of topics, the test does not tell whether they will grow up as happy and/or fulfilled adults. If the PISA tests measured presentation skills or perhaps essay writing, I'd bet USA would just leave Finland in the dust.
However, some parts of the article just fill me with dread. Child-poverty rate of 22%? That's disgraceful. Merit pay? I just can't wrap my head around that.
Also, sounds like you've gone bonkers with the standardized testing. The common complaint here is that the last year (or year and a half) of high school is too focused on the matriculation examination. I can only imagine what happens if you're tested once a year or every two years or so. You'd get nothing of substance into the young minds, only tricks and tips for the next test.
Personally I think using the metric system is more important for learning science than the instruction language. When you get down to it, the "simple Finnish words" are just as alien to everyday life as the Latino-Greek words. A word like "jännite" does not confer any more insight than "voltage". In advanced topics Finnish also uses loan words for things like electrons, momentum, grammatical cases and so on.