I'd say once the kids know the basics of math, give them access to MathCad or Maple, then let them use them to solve real-life problems.

The actual skill needed isn't to manipulate random formulae, it's describing the world in mathematical terms in the first place.

All this pen and paper stuff is really not needed beyond getting an idea about what's going on.
Either you have access to a calculator/pc, or you're doing quick sums in your head while shopping.

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‘To those who regard “crime fiction” as some sacred icon which must follow a rigid formula, I will always be the man who writes 18-syllable haiku.’Trying to make sense of computers, The Error Log.