Inch by Inch

In this lesson, children will use colored measuring worms to measure the legs of the heron in the book

Lesson for:

(See Step 5: Adapt lesson for toddlers or preschoolers.)

Content Area:


Learning Goals:

This lesson will help toddlers and preschoolers meet the following educational standards:

  • Understand patterns, relations and functions
  • Understand measurable attributes of objects and the units, systems and processes of measurement
  • Apply appropriate techniques, tools and formulas to determine measurements

Learning Targets:

After this lesson, toddlers and preschoolers should be more proficient at:

  • Sorting, classifying and ordering objects by size, number and other properties
  • Recognizing the attributes of length, volume, weight, area and time
  • Comparing and ordering objects according to these attributes
  • Understanding how to measure using nonstandard and standard units
  • Selecting an appropriate unit and tool for the attribute being measured
  • Measuring with multiple copies of units of the same size, such as paper clips laid end to end
  • Using tools to measure
  • Using repetition of a single unit to measure something larger than the unit, such as measuring the length of a room with a single meter stick
  • Developing common referents for measures to make comparisons and estimates

Inch by Inch

Lesson plan for toddlers/preschoolers

Step 1: Gather materials.

  • Inch by Inch by Leo Lionni (Go through the book and cover up the measurements with a sticky note. Once the children have measured each of the bird’s feature’s, write in the measurements. Do not use the measurements provided by the book.)
  • Enlarged copies of the various objects that the inchworm measures (robin’s tail, flamingo’s neck, toucan’s beak, heron’s legs, pheasant’s tail, hummingbird and the cover of the book)

Note: Small parts pose a choking hazard and are not appropriate for children age five or under. Be sure to choose lesson materials that meet safety requirements.

Step 2: Introduce activity.

  1. Post a picture of the heron in your meeting area. Make the inchworms available to use as measuring tools. Ask the children to estimate how many inchworms long the blades of grass are. Record their estimates.
  2. Using the blue inchworm, demonstrate how to measure the blades of grass along the sides of the blade, placing one inchworm in front of another inchworm until the blue inchworms are lined up along the entire length of the blade of grass. Write down the measurement next to the blade of grass.

Step 3: Engage children in lesson activities.

  1. Give each student a set of the enlarged copies and some inchworms. Ask the children to measure each of the bird’s features and record their results.
  2. Read the book, Inch by Inch. Pause on each of the pages that the inchworm measures (you should have a sticky note covering the inchworm’s measurement). Write down the children’s results on the sticky note. Ask the children to share and compare their results. Do this all the way through the book until you get to the “whole of the hummingbird.” Do not read the end of the book until the second read-through.
  3. Once you have gone through the book and written down the children’s measurement results, go through the book again and, using the blue inchworm, measure each of the bird’s features for an accurate measurement. Write the agreed-upon measurement on a new sticky note and cover the previous measurements.
  4. Read the end of the book aloud. Say: “And the inchworm measured and measured, inch by inch, until he inched out of sight.” Ask the children to estimate how many inchworms long it is from where they are sitting on the rug to the door, where they can exit and be “out of sight.” Record their results. Give the children the inchworms and tell them to measure the distance from their sitting spots to the door of the classroom. You might want to separate the children into small groups for this project.

Additional Extensions

  • Tell the children to use all of the different-length measuring worms and compare their results. When you pass out the enlarged copies, have a recording sheet next to each picture.

Step 4: Vocabulary.

  • Measure: Use of standard units to find out size or quantity in regard to: length, breadth, height, area, mass, weight, volume, capacity, temperature and time (e.g.,”Let’s measure how many blue inchworms long the robin’s tail is.”)
  • How many: The total or sum (e.g.,”How many blue inchworms long is the robin’s tail?”)
  • Distance: The length between two points (e.g.,”Using the blue inchworms, let’s measure the distance from where we are sitting to the door.”)
  • Estimate: To form an approximate judgment or opinion regarding the amount, worth, size, weight, etc.; calculate approximately (e.g.,”Estimate how many blue inchworms long the blade of grass is.”)
  • Inch: An imperial unit for measuring length (e.g.,”The blue inchworm is an inch long.”)

Glossary of MATH vocabulary

Early Math Glossary

Step 5: Adapt lesson for toddlers or preschoolers.

Adapt Lesson for Toddlers
Toddlers may:
  • Have trouble lining up the inchworms, one in front of the other, to measure the bird’s features
  • Put the worms in their mouths (if this is a possibility, do not use the worms with your toddlers as they pose a choking hazard)
Child care providers may:
  • Make some blue inchworms out of paper, cut them out and tell the children to glue them along the side of the bird features being measured (By gluing down the inchworms, the children will have an easier time keeping track of the number of inchworms that they have used and totaling the inchworms at the end of the activity.)
Adapt Lesson for Preschoolers
Preschoolers may:
  • Measure with one unit of measurement with ease
Child care providers may:
  • Tell the children to use all of the different-colored measuring worms and compare their results. When you pass out the enlarged copies, have a recording sheet next to each picture.

Suggested Books

  • Inch by Inch by Leo Lionni (New York: HarperCollins, 1995)

Music and Movement

Outdoor Connections

Have the children estimate and then use their inchworms to measure the length of outdoor items. For example, measure the height of the pail. Estimate how many four-inch worms high the pail is and then measure for accuracy. Then estimate how many three-inch worms high the pail is and measure for accuracy.

Web Resources

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