From: Cathy Fossum <cfossum@elite.net>
To: Teacher2Teacher Public Discussion
Date: 2003041910:33:10
Subject: dividing fractions

I agree with Rick that students need a number of concrete experiences
in understanding the concept of dividing by fractions first.  Then
they will be better prepared to understand the algorithm.   

In the example he gave, 3 divided by 3/4, I find it easiesr to
understand the algorithm when using a subtracting equal groups model
of division (as opposed to a sharing model.)  To find out how many
3/4's are in 3, first you need to know how many fourths there are.  
3 wholes X 4 fourths in each equals 12 fourths in all.  Then you need
to take out all the possible groups of 3 fourths which is dividing by
3.  Therefore, the answer is 3 X 4/3.

Actually, I just recently came to this idea at a boring teachers'
meeting.  My fifth graders already understand the concept of dividing
by fractions.  After vacation I need to give them experiences to help
them understand this algorithm.  It's intriguing to try to design
experiences that will promote this.  Any suggestions?	

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