Paper Protractors

10-31-2009, 08:46 PM
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I copy a large semi-circle for the students to cut out. I have them mark 0 at one end, and 180 at the other. We reverse the numbers and mark under the original. Then we fold it in half, mark 90 at the top, and "fit" the folded protractor into square corners (eg the corner of a textbook page), We fold again, mark 45 and 135 on top edge, and reverse the numbers and mark them under the original. We then look for things in the room that are about 45 degrees, testing with our folded protractors. You can fold one more time and make the appropriate marks.
Like a previous poster, I have them decide what type of angle they are measuring, and what the range of numbers can be. There are a couple of smart board lessons with the interactive protractor. I can send those if you need them.
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