Robert H. Bushnell, PhD. P.E.
502 Ord Drive
303-554-0827
Boulder, Colorado 80303-4732
[email protected]
Meteorologist and
Consulting Engineer
in
Solar Energy
Specialist in
SI metric units
2009 October 5
National Council of Teachers of Mathematics
Here it is metric week and I see for the first time the
NCTM position on measurement units: "provide students with
rich experiences in ... both metric and customary systems of
measurement".
Bad news. Teaching both causes smart students to see how bad
it is and give up on science and engineering. They go to the
humanities where the nonsense of two sets of units does not
show up. This leaves the USA way behind the rest of the world.
By the way, NCTM (and everybody else) should stop using the
term "customary". In the USA, metric will become "customary"
so for now the term "customary" is not meaningful. I use the
term "inch-pound". NCTM should too.
NCTM should set the following policy:
Schools shall not teach inch-pound units of measure.
Examples of units not to be taught are:
inch, foot, yard. mile,
pound, ounce,
degree Fahrenheit,
calorie, Btu.
"Not taught" means students shall not be tested about
inch-pound units and means that such units shall not be
presented as part of class room subject matter.
Teachers may respond to student's questions about inch-pound
units. Inch-pound units may be presented as part of history
but such use shall not be to find numerical values. Conversion
from inch-pound units to metric units may be used as examples
in algebra.
-------------------------
Robert H. Bushnell
