Illustrative Mathematics Grade 3, Unit 1: Understanding Multiplication and Division
In this unit, your child learns what multiplication and division mean through pictures, equal groups, and arrays. They write times sentences for what they see, share totals into equal groups, and notice that the order of factors does not change a product. Facts for 2, 5, and 10 start to come quickly. Next, multiplication meets area.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Unit 1?
- Describing pictures of equal groups with words and equations, such as 6 groups of 3 being 6 × 3. Learn more: Multiplication as equal groups
- Making sense of division as finding the number of groups or the size of each group, like 15 ÷ 5. Learn more: Division as sharing into equal groups
- Using drawings and diagrams to solve equal-group stories, and choosing whether multiplication or division fits. Learn more: Multiplying and dividing in story problems
- Seeing that 3 × 6 and 6 × 3 give the same product by turning an array a quarter turn. Learn more: Shortcuts that make times tables easier
- Practicing facts for 2, 5, and 10 until they come quickly, and connecting each one to a division fact. Learn more about knowing the times tables by heart: Knowing the times tables by heart · Learn more about dividing within 100
Sample questions to try together
These are real questions from our practice. Tap the speaker to hear one read aloud, or the light bulb for a hint, and talk about the answer together.
Question 1 of 3
Hana has 3 plates with 5 strawberries on each plate. She writes 3 × 5. What does 3 × 5 tell her?
- How many strawberries there are in all
- How many strawberries are on each plate
- How many plates she has
How you can help
- Ask your child to describe equal groups they spot at home, such as 4 chairs with 4 legs each, in words and as a times sentence (16).
- Take 15 crackers and ask your child to make 5 equal piles, then 3 equal piles, and talk about what each answer means.
- Lay out a muffin tin or egg carton and ask your child for the times sentence, then turn it sideways and ask for the new one.
Where kids can get stuck
- Drawing 6 bags of 3 for a story about 3 bags of 6, mixing up groups and group size.
- Losing track of what 15 ÷ 5 = 3 means, mixing up 3 groups with 3 in each group.
- Drawing groups of different sizes and still counting them as equal groups.
Practice makes perfect
Bobby's Math Club has practice problems that adapt to your child’s level, each with a detailed explanation and an easy-to-follow video, so your child can build confidence in these skills one step at a time.
Words your child will hear
- equal groups
- Groups that all hold the same amount, like 3 plates with 4 crackers each.
- array
- Objects arranged in equal rows and columns.
- multiply
- To find the total of equal groups.
- divide
- To share a total fairly, or to find how many equal groups fit in it.
- factor
- One of the numbers you multiply, like 4 and 6 in 4 × 6.
- product
- The number you get when you multiply two factors.
- quotient
- The answer to a division problem.
- equation
- A number sentence with an equal sign, like 6 × 4 = 24.
Want to help your child master understanding multiplication?
In Bobby's Math Club, your child practices these skills 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.
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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.
Which math standards does Illustrative Mathematics Grade 3 Unit 1 cover?
Illustrative Mathematics Grade 3 Unit 1 covers these math standards. Each one links to what it means, sample questions, and teaching strategies.
- 3.OA.A.1: Understand multiplication as equal groups, like 5 groups of 7.
- 3.OA.A.2: Understand division as sharing equally or making equal groups.
- 3.OA.A.3: Use multiplication and division within 100 to solve word problems.
- 3.OA.B.5: Break numbers apart to multiply, like 4 × 7 = (4 × 5) + (4 × 2).
- 3.OA.C.7: Know the times tables by heart, and divide within 100.
For teachers: Unit names and order vary between editions and districts, so your school’s own materials have the exact sequence. Learn how Bobby's Math Club can help your students grow.