Students are generally woefully undereducated and unaware about
applications of mathematics.
This is particularly important, as many of them (especially in Social
Sciences and the Humanities ?) will be -interpreting- numbers, not
just (or even primarily) -manipulating- them.

Imparting -understanding- is tricky, and ideally requires cooperation
(at the primary and secondary levels at least!) between math teachers
and others -- which basically doesn't happen.

I'd like history classes to include quantitative reasoning as part of
their curriculum.

----------------------------------

In a general math class (aka, calculus ;-), one can remedy this
somewhat by doing occasional studies and lectures on specific
examples.

Note that reasoning about numbers in the world is generally
statistics. There are other -applications- of math to the world, but
there the connection (e.g., dynamics, option pricing) between the math
and the world is usually tight and obvious.

I've attached a few, for starters.