I really dislike it when Japan is brought up as a comparison with the US, especially when it comes to crime or schooling. The cultures, poverty levels, and crime rates are so vastly different that it's never helpful.
Japan is a monoculture and strictly traditional, not to mention very xenophobic. Everything works because the social penalties for violating those norms are severe. It’s effectively an ethnostate and not that long ago revered their god-emperor.
The U.S. is by contrast a diverse (geographically and demographically), broad culture of immigrant communities based on a concept of rugged individualism where states and townships run things as they see fit.
If you want to reshape the U.S. in the model of Japan … well
Not to reshape America into Japan, but attempt to keep the parts that are nice while integrating the best parts of other nations. America loved to claim it was a nation of immigrants; the French even sent you a gift for how much America would take the best of other countries (the brightest minds, the hardest workers), and build with that.
Maybe that's not how the country works any more, but it was a nice fantasy.
You can legislate environment, e.g., when all you have is car-centric sprawling suburbs, it's harder to walk / cycle to school.
I grew up in a 'streetcar suburb', and was walking to school on my own (or with friends) by grade four (my dad woke me up, made breakfast, and then left for work: I knew I had to leave for school after G.I. Joe finished (at 8:30, for 9:00)).
Are they teaching 'lifestyle' - how specifically? Does the US not teach it? And do you have any evidence that homogeniety has something to do with it?
Often "homogeneity" is a dog whistle for blaming minorities.