Measuring Using Objects (Nonstandard Units)

Rulers use fixed, agreed-upon units like inches, but understanding why we need those units first requires practice with something simpler: counting repeated objects. When a child measures using objects, they are really practicing three important ideas at once:

• Lining up items with no gaps and no overlaps
• Counting accurately, one object at a time
• Comparing two counts to say which item is longer, shorter, taller, or wider

These same skills carry over directly into topics like lengths (long and short) and linear height (tall and short), where objects are compared without any measuring tool at all.

Here is the process kids follow when measuring using objects like paperclips or cubes:

1. Choose a small object to use as the measuring unit, such as a paperclip.
2. Line the measuring objects up in a row next to the item being measured.
3. Make sure each object touches the next one, with no space between them and no overlapping.
4. Count the total number of objects used.
5. Say the measurement as a number of objects, for example, "the pencil is 5 paperclips long."

Example: Measuring a Pencil With Paperclips

Imagine a pencil is measured by lining up paperclips underneath it, end to end, until the row is the same length as the pencil.

Since there are 5 paperclips lined up along the pencil with no gaps, the pencil measures 5 paperclips long. If a bigger object, like a crayon, were used instead, the count would be a different number, even though the pencil itself has not changed size. This is why the type of object used to measure always matters when describing a nonstandard measurement.

Measuring using objects becomes even more useful when comparing two items. Suppose a crayon is measured with the same paperclips and comes out to 3 paperclips long, while the pencil measured 5 paperclips long. Since 5 is greater than 3, the pencil is longer than the crayon. The key rule is that both items must be measured with the same kind of object; comparing a count of paperclips to a count of blocks would not give a fair comparison.

This counting-and-comparing approach also applies beyond simple length. The same idea of counting objects is used when comparing how much space something takes up sideways, as in width (wide and narrow), and when comparing how much a container can hold, as in capacity (holds more, holds less).

• Use identical objects for the measuring units, such as all the same size cube or paperclip.
• Leave no spaces between the objects and do not let them overlap.
• Start measuring from one end of the object being measured.
• Count carefully and point to each object as it is counted, so none are missed or counted twice.
• Remember that switching to a different measuring object changes the count, even if the item being measured stays the same size.

Measuring using objects gives young learners a hands-on way to understand length before formal units are introduced. It also strengthens counting, one-to-one correspondence, and comparison, all of which are foundational for later math topics. These same comparison ideas reappear when looking at mass, since heavier and lighter objects can also be compared using simple balancing tools and counting, just like in nonstandard length measurement.

Related lessons

• Kindergarten