Circle Graphs have my Students' Heads Spinning! ```Name: Name Status: N/A Age: N/A Location: N/A Country: N/A Date: Around 1993 ``` Question: I am currently in a teaching program. Last week I began a part of my practicum that has us teaching one lesson per week in the assigned school. My cooperating teacher asked me to introduce circle graphs to her sixth graders. She told me the students were familiar with the process of converting fractions to decimals and vice versa. One third of the way through my lesson, I realized the majority of the students had no concept of how to do this. I retaught the conversion process and then again had them look at circle graphs, yet they still remained confused. How can I better illustrate the circle graph concept and even the fraction to decimal conversion so my future students will understand? Any suggestions will be greatly appreciated. Thank you for your time, and I apologize for the lengthy scenario before my question. Replies: I believe a circle graph is just a pie chart showing a fraction so a pie cut once through the middle demonstrates 1/2 = 0.5, etc. As for the fraction to decimal conversion, I cannot think of any methods other than the plain old fashioned long division. Of course, once you know that 1/8 = 0.125, then you know that 3/8 = 3 * 0.125 = 0.375 without having to do the long division. Hope this helps! John Hawley Hawley's hint about how to use 1/8 to get 3/8 is a nice use of pattern matching. But fundamentally, how will the students understand the "circle graph" idea? Basically, it is better to describe it as a pie chart because then students can visualize cutting it up just as if it were a pie. One way to get the concept across might be to cut up some cardboard "pies" into pieces; cut up one into thirds, one into fourths, fifths, eighths, and so forth...another would be to split up into groups of 5, hand each group a pie, and tell them to draw a piece of paper from a hat. One piece of paper would say 3/8 and the rest would say 1/8. Or, better yet, one could say 0.375 and the others 0.125. Then have them divide up the pie (or pizza) according to the numbers they drew. Hope this helps. Topper Click here to return to the Mathematics Archives

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