3rd Grade · Operations & Algebraic Thinking
3.OA.C.7: Know the times tables by heart, and divide within 100
3.OA.C.7 is a 3rd grade Common Core math standard in Operations & Algebraic Thinking. 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
Fluently multiply and divide within 100, using strategies such as the relationship between multiplication and division (e.g., knowing that 8 x 5 = 40 one knows 40 ÷ 5 = 8) or properties of operations. By the end of Grade 3, know from memory all products of two one-digit numbers.
In plain words
Know the times tables by heart, and divide within 100.
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 6
How many small squares are in this array?
- 10
- 24
- 30
Where students can get stuck
Know the times tables by heart.
- Confusing facts that sound or look alike, such as saying 6 x 8 is 42 or mixing up 7 x 8 and 7 x 6.
- Counting up from the start for every fact, so 7 x 9 means saying 9, 18, 27, 36, 45, 54, 63 each time.
- Knowing the facts in order when chanting a table, but not when one like 6 x 9 is asked on its own.
Divide within 100.
- Thinking division works in either order, the way multiplication does, so 3 ÷ 12 and 12 ÷ 3 seem to have the same answer.
- Counting up by 8s and losing track of the jumps, so 72 ÷ 8 comes out as 8 or 10 instead of 9.
- Mixing up 0 and 1 in division, saying 6 ÷ 6 is 0 instead of 1.
Effective teaching strategies
- Practice a few new facts at a time in short, frequent sessions, starting from the facts students already know and working outward.
- Teach strategies for hard facts, such as doubling a 4s fact to find the 8s fact, or adding one more group to a 5s fact to find the 6s fact.
- Mix up the order of facts while practicing, so students recall 6 × 9 on its own and not only in the chanted sequence.
Units that teach this standard
Find where 3.OA.C.7 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.
Bridges in Mathematics
enVision Mathematics
Eureka Math
Eureka Math²
Everyday Mathematics
Go Math!
i-Ready Classroom Mathematics
Illustrative Mathematics
Math Expressions
Don’t see your curriculum? Contact Bobby and we’ll see if we can help!
Share it with families
Each skill has its own guide for families, with a plain-language look at the skill, three questions to try together, and ideas for helping at home.
Help every student practice problem solving 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.