Join tenths and hundredths
Use equal-sized hundredths to combine two measured amounts.
Explore this lesson →9 practice questions · Optional read aloud · Thinking pad
Let’s understand the idea.
- Rename tenths as hundredths before joining the pieces.
- Both sources keep the same measured whole.
- A total can cross into another whole without changing the size of each hundredth.
Something to notice
Ask the learner to point to the whole, a tenth and a hundredth. Can they explain why splitting keeps the amount unchanged, while joining a second source can increase it? Ask for a fresh example without demonstrating the entries. Physical, oral, child and educator observations remain pending.
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.NF · 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.