[tjr]

I don't know how calculators are used in classrooms today, but when I was going through school, the general idea was that we could use calculators to do tasks that we had already learned to do.

E.g., we could not use a calculator at all when learning arithmetic.

Once we learned arithmetic and were learning (say) algebra, we could use the calculator to do arithmetic, but not to compute the algebra for us.

While learning trigonometry, we could use the calculator for arithmetic, but not for computing sines and cosines.

While learning calculus, we could use the calculator for arithmetic and sines and cosines, but we could not use it to perform integration or differentiation for us.

And so on.