I’m a teacher in the Japanese school system, so I’ll weigh in here.
Students are generally exposed to traditional music and culture in the context of events or as part of a broad curriculum. However, it’s generally not a class focus outside of a few stand-outs.
To give you a clearer idea, students may learn to play Sakura Sakura or Kokiriko as part of a music class. Sometimes, this may just be on a recorder. Rarely, this may be on more traditional instruments. At my current school, the first years just finished learning Kokiriko - but the arrangement is more choral than min’yo and oriented around piano with traditional instruments (kane, taiko, kokiriko, and sasara) serving as accompaniment.
Traditional art clubs, Kyoudogeino-bu, or wagakki clubs, such as Koto, are the usual hot-spots for traditional music in schools. These tend to crop in places with strong musical traditions.
Occasionally, they are paired with a class/experience based class in the first year. At my previous school, first year students were obliged to practice local min’yo and their accompanying dance. Students who were interested in them could further pursue their interest via the club.
At another previous school students were taught koto as part of the music curriculum in late winter, but beyond that there wasn’t much exposure.
At a colleague’s school, there is no such mandated activity - but there is a Koto club that hires a licensed koto teacher to instruct interested students.
Outside of the school and club system, there are independent performance, practice, and preservation groups that tend to focus on a singular piece of music or instrument.