Referring page: http://www.nctm.org/about/content.aspx?id=6346
The explanation offers no reasons why the customary units should be taught. The result of trying to teach two conflicting sets of measuring units for over 30 years has been a people who cannot compute or measure well. I know a Colombian girl whose parents entered the US before she entered school, and who does not know her own height in meters. I am a son of immigrants, started my schooling a few years before the metric system was introduced in the schools, have never known my mass except in kilograms, and routinely do geometrical calculations in my work. I've also met people studying in college to be civil engineers or surveyors who had trouble with the mathematics involved. I recommend the following changes: *No measuring devices capable of measuring non-metric units, except for time and angle, shall be allowed in the classroom. *Mass and weight shall be distinguished. *With the exception of time and angle, problems shall not use only non-metric units, and at least half of all problems that involve units shall be entirely in metric units. *Non-metric units shall be presented only as defined in terms of metric units, and only exact conversions shall be used. E.g. an inch may be presented as 25.4 millimeters, but no ruler marked in inches may be used. It shall not be necessary to teach non-metric units. The degree may be excepted, since its conversion factor is irrational. *Practical examples, such as comparing two packages of strawberries whose prices and masses are given, shall be presented in metric units and only in metric units. This includes commodities such as gasoline which are currently sold only in non-metric units. All problems involving such commodities must measure them in metric units. Pierre Abbat -- Don't buy a French car in Holland. It may be a citroen.
