2nd Grade · Measurement & Data
2.MD.B.6: Represent whole numbers as lengths from 0 on a number line diagram
2.MD.B.6 is a 2nd grade Common Core math standard in Measurement & Data. Here’s what it really covers, and how you can help your students learn it.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
The standard
Represent whole numbers as lengths from 0 on a number line diagram with equally spaced points corresponding to the numbers 0, 1, 2, ..., and represent whole-number sums and differences within 100 on a number line diagram.
In plain words
Represent whole numbers as lengths from 0 on a number line diagram.
Sample questions from student practice
These questions from Bobby's Math Club are the kinds of questions your students will see. You can try answering them to see what a student might see.
Question 1 of 3
On a number line from 0 to 10, which number is closest to 0?
- 5
- 1
- 10
Where students can get stuck
- Counting marks instead of jumps, including the starting number, so 35 + 6 lands on 40 instead of 41.
- Spacing the marks unevenly, so distances look wrong and equal jumps appear different sizes.
- Moving the wrong way, jumping right to subtract or left to add, especially on unlabeled lines.
Effective teaching strategies
- Have students use grid paper squares to space the marks of a number line evenly, starting at 0, so each number names the length from 0 to that mark.
- Model 35 + 6 by starting at 35 and drawing 6 hops while counting 36, 37, 38, 39, 40, 41, so students do not count the starting number.
- Ask students which way to move before they draw, right to add and left to subtract, and have them check with the matching equation, such as 41 - 6 = 35.
Units that teach this standard
Find where 2.MD.B.6 lands in the program you teach. Each unit has a guide written for families. Unit names and order vary between editions and districts, so your school’s own materials have the exact sequence.
enVision Mathematics
Eureka Math
Eureka Math²
Everyday Mathematics
i-Ready Classroom Mathematics
Illustrative Mathematics
Don’t see your curriculum? Contact Bobby and we’ll see if we can help!
Share it with families
Families can read Adding and subtracting on a number line for a plain-language look at this skill, with three questions to try together and ideas for helping at home.
Help every student practice measurement and data at home
In Bobby's Math Club, students practice at just the right level, with a hint when they need one, a clear explanation after every question, and kid-friendly videos. Unlimited practice is free for every family.
See how it works for teachers
Written by Robert “Bobby” Barnett
Bobby is an award-winning math teacher, the author of Meet Every Learner’s Needs, and the father of two elementary-school math learners. He uses Bobby’s Math Club with his own kids a few times every week. Learn more or contact Bobby.