Mathematics·Number Representation & Place Value·procedural
10 More or 10 Less
Mentally find 10 more or 10 less than a given two-digit number without counting
Suggested ages 6–7
Learning journey
Your child is learning how numbers work by understanding place value — discovering that in two-digit numbers, each digit has a different value depending on whether it represents tens or ones.
Evidence of understanding
- Given 56, quickly say 66 is 10 more and 46 is 10 less
- Explain that adding 10 increases the tens digit by 1
- Answer '10 more than 73' without using fingers or counting on
Assessment prompt
Can 10 More or 10 Less quickly tell you what is 10 more than 43 or 10 less than 71 — without counting up or down one at a time?
Standards alignment
1.NBT.5US · ccss-math
Mentally find 10 more or 10 less
Common Core State Standards for Mathematics · 1