One unit, then another
Measure a length with equal units placed end to end.
Explore this lesson →8 practice questions · Optional read aloud · Thinking pad
Let’s understand the idea.
- Begin at one end and place equal-length units along the whole object.
- Leave no gaps, and do not overlap the units. Count the units, not their edges.
- For the same ribbon, a longer unit means fewer units are needed. Always say which unit you used.
Try it. Change it. Explain it.
Open the lesson to use its pictures and controls. In How it works, connect the picture to the idea. In Play & discover, change the quantities and notice what stays the same. In Your turn, answer questions and use the explanation to check your reasoning.
You can ask for help, draw on the thinking pad, or listen to the question and answer options. Progress distinguishes independent work from work completed with help.
Let’s try it →Curriculum connection
Grade 1 · 1.MD · US Common Core
This lesson is mapped to these standards. A completed activity is practice evidence, not a claim of mastery. Content is checked against the linked official standards and its mathematical models are tested.