Students and teachers alike will appreciate the very helpful Dictionary of Units Web Site. As part of the Centre for Innovation in Mathematics Teaching, the site "provides a summary of most of the units of measurement to be found in use around the world today (and a few of historical interest), together with the appropriate conversion factors needed to change them into a 'standard' unit of the Systeme International." The single (long) page contains everything a student would need to figure out a scientific conversion and understand different systems of measurement, as well as other historical and interesting facts about "Metrication."
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