Exchange pieces, keep the amount
Change the count of place units without changing the measured amount.
Explore this lesson →8 practice questions · Optional read aloud · Thinking pad
Let’s understand the idea.
- Ten equal smaller units make one neighboring larger unit.
- An exchange preserves the original amount and all leftovers.
- Moving an unchanged number of markers to a different place changes the amount instead.
Something to notice
Ask the learner to choose a new repeated-digit example and explain the place-unit amounts. Then ask them to distinguish an equal-value exchange from moving an unchanged marker count. Listen for the fixed whole and preserved leftovers.
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 5 · 5.NBT · 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.