Linear Measures, Weight, and Volume
Examples of standards measuressuch as a growth chart, weight scale, or masking tape on the floor to mark off distances in inches or feetshould be displayed and used to build awareness of linear measures (length, width, height). Children should be encouraged during play to describe nonstandard measurements, such as “How many blocks long/high is your castle?” (Charlesworth 2005.)
Activities for linear measurement can include:
- Using any long object (crayon, paper clip, straws, pipe cleaners, string) to measure objects or distances (classroom dimensions, rugs, furniture, height of children, etc.)
- Filling up cups, quart/liter/gallon containers with liquids or sand
- Counting the number of marbles it takes to fill different-sized jars
- Comparing measurements of objects in terms of longer, shorter, wider, narrower, etc.
- Cooking activities
- Using a balance to compare the weights of different objects and combinations of objects
- Pacing off longer distances such as the length of a hallway, sidewalk, or rows in the garden
- Using standard measurement tools such as rulers, yardsticks, or a tape measure
The Twenty-Four Foot Python: A Teachable Moment about Measurement
Ms. Deanna was working her way through Shel Silverstein’s book Light in the Attic (1981, p. 44) with her preschool/kindergarten class when she came to “Snake Problem”:
It’s not that I don’t care for snakes,
But oh what do you do
When a 24-foot python says . . .
I love you.
The poem prompted an animated discussion about how long a twenty-four-foot python would be. Many ideas were suggested, but they could not agree on a single answer. Ms. Deanna decided to follow up, asking what they could do to find out. The children said they wanted to make a twenty-four-foot-long paper python model. It became evident that the focus of the investigation was going to be accuracyexactly twenty-four feet, not an inch shorter or longer! Ms. Deanna produced a ruler, introducing it as a standard unit of measure for one foot. Using the ruler, the children quickly realized the classroom floor tiles all measured exactly one foot square. They spent several hours measuring off distances in the classroom in floor tiles but found that no matter how they measured, there was no twenty-four-foot space in which they could build their model.
Betty, in a flash of insight during a conversation about the problem said, “I know! The hallway is really long. What if we build it in the hallway?” They used masking tape to mark off the beginning and end of twenty-four feet and commenced building the python out of white mural paper, stuffing it with crumpled newspaper. They pored over books and online pictures of pythons to get an idea of how big the head should be in relation to the body. They “amputated” the first head they made when they realized it was too large proportionally and made a smaller one that was “just right.” They painted the python to replicate the coloring patterns they found in their pictures.
The children carried the python to show it to their friends in another classroom, and it lived a long life in their classroom, since Ms. Deanna hung it from the ceiling, where it became a frequent source of reference in other conversations about measurement and snakes.