kamikiri, 紙切り, like the snowflakes we used to make by folding and cutting, but more advanced. It's easy to teach because no matter what you do you'll end up with some kind of repeated pattern. This is a great craft, and it's clear there are several different folding and cutting techniques just in that one photo in the OP.
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The grown up version of this is Ise Katagami, 伊勢型紙, where laquered paper is cut to create silk screen patterns. Artisans make their own tools to achieve different kinds of cuts. Near Ise (Suzuka), there's an Ise Katagami museum.
The different way people live in Japan is as varied as it is in the UK, depending on their age and style and economic situation. I'd watch Japanese source material to try to get a feel for these things; it's hard to describe exactly how small and cramped some of those living spaces can get in the city, or just how different that is to grandma's house in the boonies; the living spaces that make Japanese homes look airy and spacious are mostly fantasy, but it's a pleasant one.
I think it's akin to like Full House... a single dad (who doesn't seem to work very much) supporting a huge family in a massive, well-kept San Francisco victorian, that hasn't been subdivided into a multi-unit apartment. It provided a great set for the show, with lots of different spaces for filming scenes. The set, the dwelling, becomes a character in the show, in a way. But it's also a wildly unrealistic presentation of an American household.
Depending on how convincing you want to be, a native/cultural consultant should be budgeted for in production to help with the details. Honestly the most Japanese thing you can do is pay attention to the details; otherwise it will be obvious to the audience who know better--that you're just using the
idea of Japan as a prop. It's always a gamble producers are going to take, because THEY don't know the difference, and they don't respect their audience. Someone on hand to say "uhhh don't use that erhu music, what's wrong with you?" can help save them from their own ignorance.