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Hi, I currently teach a math course for elementary education majors. As we discussed converting metric units of length a student said she learned the following mnemonic sentence to aid in remembering the metric prefixes and relationship to the base unit - meter: Kangaroos Hop Down My Drive Christmas Morning km hm dam m dm cm mm She went on to say her grade school teacher her taught her to convert by: 1) writing out this sentence 2) writing the ones digit of the measurement you're starting with in the column under that unit 3) write any tens or greater digits each in a column to the left of your starting unit 4) then to convert write add zeros to the left or right our your original number to fill in empty columns until you reach the column of the unit you want to convert to. So to convert 35 cm to m I'd write: K H D M D C M 0. 3 5 Thus, 35 cm = 0.35 m Seems intuitive to me and I tried to present this with the student in our next class but there was a lot of confusion on where to put the decimal place. I explained the decimal always goes after the ones digit but that didn't seem to sink in - has anyone heard of a charting the pattern type method like this for teaching conversion and if so, any suggestions? We've tried talking about moving the decimal point in the measurement number based on steps up or down in the metric units but that got a bunch of blank stares too. I'm trying to break this down as simply as possible and am hoping someone has had experience with this method and can offer input/advice. Thank you.
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