In article , jj wrote:
what about high school math/science? would kids be taught in Metric
measurements? Would most young people know how big a metre, or a kilogram
is?

In physics, it was. Even for general science in the 7th grade, the metric
system was taught as units of measurement and was practised consistently
throughout the entire year. It is possible it is taught in earlier grades
elsewhere. (Note: I am speaking of a public school education; it _may_ be
different or better with private schools.)

I don't recall any math courses up to the early 1990s having ever used the
metric system -- and I've been to at least 10+ different schools -- which
is likely a reflection on the curriculum standards adopted by the local
board of education with an eye toward usability in one's immediate
surroundings (city, state, country).

With the more advanced math courses, things tend to become
unit-independent in explaining the theory and derivation, such as calculus.
Specific application of that for locally used units is left as an exercise
for the reader, so to speak.

If you asked the average metric-familiar person on the street for specific
dimensions in metres (or other forms of measurements in the metric system),
they might have to think for a few moments or find conversion factors, but
they would likely eventually come to an answer within the general vicinty,
or even exactly right.

Of course, I should mention that I don't really have a good idea of how
many people are familiar or comfortable with the metric system in the U.S.
So I only speak of these who *do* know something about the metric system.

I could certainly give you reasonably acceptable answers if it involves
meters, kilometers, kph, litres, degrees celsius (centigrade), kilograms,
or some such... it's just the really small units that I can roughly guess
the magnitude of but need a little more time to make a more accurate guess
on the conversion. Given a little time to look up the conversion factors, I
can give you a perfect answer every single time :-)

-Dan