Sometimes Comparing is a Good Thing: Getting Hands-On with Early Childhood Measurement
Do you have a wall like this in your house?
My parents were fantastic about maintaining our family's “height wall” when I was growing up.
I loved this record of my siblings’ growth, especially when I passed up my older sister, Jen, on October 10, 1986. Note: I may be taller, but she's much cooler!
One of my regrets as a mom of 8 kids (in addition to not teaching them to do their own laundry as soon as their arm was long enough to reach into the washer) is not making a “growth wall” by recording their heights on a door jam.
I blinked, and they were taller than I am!
So, I’m starting today with the 6 boys who are still living at home. It’s kind of hokey, and they hate it (notice Zeb's pained expression in the photo below), but I realized I didn’t have to continue beating myself up about skipping it with the older kids; I can start now!
If you look closely at my parents' "height wall,” you’ll notice there are no standard units indicated. Instead, the marks show only growth over time, which allows for comparisons between the four kids who grew up in my family.
Comparison is the beginning point of measurement.
Preschoolers’ initial ideas about measurement naturally focus on direct comparisons between two objects. They holler, “She got a fatter cookie than I did.” or “I can run faster than you can.”
Young children’s comparisons should be number-free initially (e.g., longer, shorter, heavier, lighter, faster, slower) and involve only two objects for comparison before comparing multiple objects.
When people think of measurement, they often think of linear (length) measurement first.
Clay Worm Comparisons is a fun activity that explore linear measurement comparisons and builds kids' hand muscles and fine motor skills.
Clay Worm Comparisons
You can watch of video of this activity here.
What you need: playdough or clay, paper, crayons, activity sheet (available here)
Instructions: Roll the clay into worms then lay a worm on top of each drawing.
Take the clay worms off the drawings. Lay the worms on a blank sheet of paper in order from shortest to longest.
Trace around the worms to make a permanent record of your results.
Label one end of the paper SHORTEST. Label the other end of the paper LONGEST.
But length isn’t the only type of measurement we can explore with young kids. With the right tools, kids can make sense of weight comparisons too.
Do you have a pan balance? It's the perfect tool for making comparisons of weight without worrying about exact numbers. It costs less than $20 and promises hours of math investigation without a lot of work on your part. For a simple exploration comparing weights, try Potato Comparisons.
What you need: six potatoes (labeled A through F), pan balance
The Problem: If you were making baked potatoes for dinner, how could you be sure that the children get lighter potatoes and the adults get heavier potatoes?
Instructions: First hold the potatoes and place them in order on the table from heaviest to lightest. If you want to, you can record your guess by listing the potatoes’ letters on a sheet of paper. Then use the pan balance to check your guess.
Capacity (or volume) provides another area of measurement for young mathematicians to explore.
Capacity is a measure of "how much something holds." Young children explore this naturally during their play with blocks and other toys, but if you’re looking for a simple activity for comparing capacity, you'll love Capacity Sort.
To watch this activity in action, check out my son, Knox, giving it a shot here.
What you need: 3-5 labeled containers of different sizes and shapes (label one of the containers as your target) dry beans, paper cup, signs reading HOLDS MORE THAN, HOLDS LESS THAN, HOLDS ABOUT THE SAME
Instructions: Look at the containers. One container is marked with the word “target.” Your job is to sort the containers into three groups: HOLDS MORE THAN, HOLDS LESS THAN, or HOLDS ABOUT THE SAME amount as the target container.
First make a guess about how you would sort the containers.
Then check your guesses by using the cup to fill the target container with dry beans. How many scoops did the target container hold?
Finally, count the scoops it takes to fill each of the other containers. Were your guesses correct?
Measurement should be taught using hands-on materials that support conceptual understanding.
Get out the playdough, beans, pan balance, and potatoes and watch your kids connect measurement to their own experiences and interests.
I hope you enjoy these simple activities for building young children’s math-positive mindsets about measurement. For more measurement ideas, check out Chapter 7 of my book Math-Positive Mindsets: Growing a Child’s Mind without Losing Yours. And watch for an upcoming blog post about the next stage of measurement understanding-- nonstandard units. Who knew cotton balls and paper clips held such mathematical potential?