When I think about the problems of the education system in Europe and Japan, it strikes me that they are completely different, even opposite problems.

Nowadays, the main issues with schools in Europe is in the relation between teachers and students. There are personality and value conflicts. Some teachers are also not made to be teacher, or lack pedagogy or authority. Some students, especially in lower class milieux, skip school or cause trouble in class because they just don't care, or can't control themselves (esp. adolescents still struggling to master their hormonal impulses). But I don't think there are any serious issue regarding the qualification and actual knowledge of the teachers, nor in the curriculum itself (apart from compulsory religion classes, in Belgium at least).

The problems in Japan are not really in the teacher-student relations. This is mostly due to the Japanese culture's emphasis on harmony and avoidance of conflict. Students are much quieter than in Western countries. It is even a common sight to see many of them sleeping on their benches. But they rarely come into direct conflicts with their teacher, or cause serious troubles, and the teachers also let them sleep indiferrently. In my experience, teachers in Europe would wake up and scold anybody bold enough not to listen carefully to what they say. This attitude is more conflictual, less passive and indifferent, and is naturally in part responsible for the problems.

European teachers tend to be stricter in tests and examinations too. There is no way all the class would pass if they didn't know sufficiently their subjects. In Japan, again to avoid to break the group harmony and cause conflicts, all students pass, even if they constantly give back a blank sheet at the tests.
Japan's main problem is, I believe, in the knowledge and qualifications of its teachers. While it would be unthinkable in most/all European countries for a secondary school teacher not to have a 4 or 5-year university degree in the field they teach, it is common for Japanese secondary school teachers to teach many subjects, and some completely unrelated to their field of expertise. There are countless Japanese teachers of English who cannot even speak English, and teach mistaken grammar and a katakana pronuciation. No wonder the Japanese ranked 2nd to last after North Korea in the world's average TOIEC scores (see my replies in this thread).

Then, many Japanese teachers are visibly incapable of teaching world history or geography without including false information and mistaken stereotypes about foreign countries. No wonder if they did not graduate in history and geography, respectively. I believe it would be more beneficial for the students not to be taught English, world history or geography at all than to learn plenty of mistakes.

Even the Japanese recognise the great deficiencies of their school system, and the need for children to attend private cram schools after school, if they want to learn a bit more efficiently, or just pass university entrance exams. This also explains why Japan is the country with the most private English schools in the world, despite (or justly because of) the gross inability of most of its inhabitants to speak decent English. Look at Singapore, where most people can speak fairly good (or even excellent) English in addition to their mother-tongue (be it a Chinese dialect, Malaysian or Tamil). Look at India, where even unschooled children speak conversational English, and middle-class to upper-class people usually speak it with a vocabulary and grammar reaching near Native levels.

The Japanese education system also notoriously fails to stimualte students and give them the envy to learn and think by themselves. On the contrary, in Europe, learning by oneself (more than required by the teacher) and thinking critically and independently is highly valued.

In conclusion, while Europe's education problems are mostly in the teacher-students relations, and more a problem of pedagogy, excessive strictness and excess or lack of authority, Japan's education problems are mostly about its teachers' competencies and lack of strictness, and the general indifference of both teachers and students toward learning.