Trupmenos. http://artistryofeducation.blogspot.com/2014/07/the-magnified-inch-for-fractions.html

The Magnified Inch for Fractions

I heard about the Magnified Inch lesson from a colleague about ten years ago and then read about it in a book called Family Math.  The authors put this lesson in the measurement category, but I find it helpful when teaching fractions.  Here is my version of the lesson:

I start by cutting an eighteen inch strip of construction paper for each student.  ( I always make extras.)  I have students fold the ends together to make half.  I label it with a fairly long line, but I leave enough room to show equivalent fractions.

Next, I have the students fold each end to the center.  We talk about cutting each half into half.  I label each part with a slightly shorter line like you would see on a ruler and mark the lines 1/4 and 3/4 respectively.  I tell them that 2/4 is the same thing as 1/2 and write in that label as well.

The next part is where I lose some students.  I need to fold each fourth into half.  I have found that the simplest way to do this is to fold each end of the strip to the 1/4 mark and then to the 3/4 mark.  I label the new marks 1/8, 3/8, 5/8 and 7/8.  I explain that 2/8 = 1/4, 4/8= 2/4=1/2, and 6/8 = 3/4.  Decide how much guidance your students need with labeling equivalent fractions based on how much experience they have had.

I use this tool as a number line.  We talk about which fractions are greater or less than others.  I let them use it as a tool as we go through the unit. I find that because my students have created this tool, they understand it better than a number line printed in a book.