I think this topic is too complicated to discuss over text like this.

I agree with you, I’m sure we think similarly, and it seems like talking to children about mindfulness could be amazing.

I fear that many schools/teachers won’t do a good job at it, judging exclusively from my own experience back in school... but that’s a different issue.

Yes, in an utopia, this class may be useless.

There are still many places on a planet where kids are not burdened by depression and sadness. It happens to them as well, of course, but not in any extraordinary amounts.

Most kids in the UK don't need to know multiplication to get their basics fulfilled either. Most of schooling is about preparing them for the future, not for the present. But some will benefit sooner, and you can't always tell which ones.