This little boy was trying to figure out if his two towers of pegs were the same height.  It was really hard because they were so long that they were bending and curving, so their actual lengths were not readily apparent.

His teacher helped him by holding the base of the towers so he could try and hold them straight and then compare them.  She was asking him leading questions that helped him think about how he could compare them, what he wanted her to do to help, and ultimately figure out which one was taller.

At some point, I might have asked him to count the pegs, but that would have been a very difficult task.  Using the pegs as a non standard unit of measure, he could have explored how many pegs each tower had and then considered which one had more, which would then mean “taller”.  However, one-to-one correspondence is really hard when each unit is attached to another.  It is hard to discriminate between the pegs and the colors (it may have been easier if every peg were a different color).

I think he did a great job trying to get them to stand up straight so he could look and see which one was taller.  How would you have helped him figure this out?

When I was growing up my parents measured my sisters and I against the door jamb of the kitchen.  You could see our upward progress with names and dates.  I remember thinking that leaving that evidence of our growth was so sad when we moved out of my childhood home.  My husband and I have done exactly the same thing with our kids.  When I look at it now, I can’t believe that they were ever so small.

You can measure your kids on the wall (covered with a piece of paper) and make marks to show each child’s height.  You might place each child’s picture next to her/his mark so they can see themselves.  This now means that the children can compare the heights of the children in their group.

Here is a link to a lesson plan that involves length measurement using a nonstandard unit of measure.