>TL;DR learn a /scripting/ language relevant to your interests (because you're more likely to stick with it if it interests you), and don't sweat the math until you absolutely have to
Yeah, it's pretty amazing what you can do with a little Ruby, Python, or Javascript, with maybe a year or two of casual study and practice. That's about the level of programming ability that most people should have.
Ideally, some HTML/CSS and SQL on top of that so you can build a basic "full-stack" CRUD app, or customize a basic framework (Rails or similar) app.
That level of knowledge would make millions of non-programmer workers vastly more efficient at their jobs, but there isn't really any need for most people to go any deeper than that.
I, for one, think that everyone should learn practical basic statistical analysis skills.
I also disagree with the "learn math!" crys of developers; I rarely find myself using more than basic algebra (variable substitution) in most tasks, and you don't get into the abstract calculus stuff until you're working on solving graph problems, /which is usually a bad idea/ because some researcher already has a better algorithm than you're thinking of using for the given problem. I would also assume that "learn to code!" doesn't mean "learn pointer math and understand how to balance a b-tree!", so let's not pretend that those kinds of things will matter to beginners.
TL;DR learn a /scripting/ language relevant to your interests (because you're more likely to stick with it if it interests you), and don't sweat the math until you absolutely have to. I would argue that /grammar/ is much more important in programming and understanding verbs vs. nouns is of great importance.
If we could get every sports fan to learn how to work a spreadsheet to track their favourite teams and be able to calculate the odds of X team beating Y team, I feel like the world might be just a tiny bit better.
If we could get single parents to learn how to project grocery costs and compounded interest on not paying that credit card bill this month in favor of buying ______ (ignoring how awful that situation is), I feel like the world might be just a tiny bit better.
If teachers had systems to conveniently track student homework completion / success rates, they may be able to more efficiently target their lessons to focus on those topics where students did the worse, and I feel like the world might be just a tiny bit better.
I'd also argue that "Personal Finance" and "Common Legal Matters" would be incredibly useful classes as /required/ for highschool graduation.