Natasa's comments on the article by Sue Lamon were telling enough to get me read this carefully. She talked about the research using 6 classrooms where 1 class was taught fractions traditionally and the other 5 were all taught/learned fractions through some other method than parts of a whole. The 5 non-traditional classes all performed better on an assessment of their proportional reasoning than the control class. While I have been able to reason out problems from my own grasp, I was challenged by how unfluent I was in describing the other methods. I'm going to publish a few of problems they pose as an example of this thinking.
1.) Does the shaded area show 1 (3/8 pie), 3 (1/8 pies), or 1 1/2 (1/4 pies)? Does it matter?
[the shaded region was 3 sectors of a circle divided into 8 equal sectors]
2.) You have 16 candies. You divide them into 4 groups, select one group, and make it three times its size. What single operation would have accomplished the same result?
4.) If it takes 9 people 1 1/2 hours to do a job, how long will it take 6 people to do it?
5.) Without using common denominators, name three fractions between 7/9 and 7/8
6.) Yesterday Alicia jogged 2 lapps around the track in 5 minutes, and today she jogged 3 laps around the track in 8 minutes. On her faster day, assuming that she could maintain her pace, how long would it have taken her to run 5 laps?
7.) Here are the dimensions of some photos: (a) 9 cm x 10 cm, (b) 10 cm x 12 cm, (c) 6 cm x 8 cm, (d) 5 cm x 6.5 cm, and (e) 8 cm x 9.6 cm. Which one might be an enlargement of which other one?
Think of the nuances these represent?
My grade 8 classes this year have really exposed the gaps in this understanding:
For example: One case contains 8 cans. How many cans are in 3 cases? How many cans are in 2 3/4 cases?
Most could do the first question correctly. A common answer for the second question expectedly was 19 but some had answers of 40??? Clearly, I hadn't created learning in this area. The next period I had them again draw out the cases showing the cans in the cases. This simple improvement with a concrete example made it possible for the students to do much harder examples successfully.
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