Fix the written step
Repair a highlighted entry and identify its place-value meaning.
Explore this lesson →8 practice questions · Optional read aloud · Thinking pad
Let’s understand the idea.
- A highlighted entry can be wrong even when nearby entries look familiar.
- Use the original operands and unit values to check a carried unit, prepared top count or result digit.
- Composition and decomposition keep the amount unchanged; subtraction removes a stated amount.
- A zero can be an essential result digit. After repairing a step, check the full calculation by its inverse.
Something to notice
Ask the learner why the highlighted correction is necessary, then invite them to explain it without reading the entry-meaning choices. Most of the supplied record is given support: repairing one field does not mean the entire method was produced independently.
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 4 · 4.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.