I don't think there is any other country with such strong educational standards as Japan, perhaps.
At least none of the teachers in Japan have ever heard of the Courses of Study.
Thanks to the Courses of Study, students can transfer to any school in Japan and receive the same standard of education.
On the other hand, however, it becomes difficult to develop an education that meets the individual needs of students with significantly higher or lower academic ability.
Also, even if teachers and schools want to provide education with special content, it is difficult to do so.
This is because teaching the content of the Courses of Study fills up a certain amount of teaching time, and there is not much time left for options.
This makes it difficult to implement an immersion program.
It requires a certain level of student achievement and sufficient teaching time.
(And the competence of the teachers...weep)
My feeling is that if you are going to do immersion in science, you need at least 1.5 times the standard time allotted.
I want them to check new vocabulary, study (in English, of course, so I will do it slower and more carefully than in Japanese), and finally, I want them to write experiments and essays.
That would require a lot of spare time.
We also need to cut down the content to some extent.
Immersion classes are basically taught by foreign instructors, but I wonder if they understand that Japan has its own curriculum guidelines and that they must follow them.
Do the Japanese instructors who support them fully understand the Courses of Study, and are they able to tell the foreign instructors what they need to teach and what they do not need to teach?
Japanese teachers are too busy to do all these things perfectly.
Translated with www.DeepL.com/Translator (free version)