Reveal Math Grade 5, Unit 4: Multiplication of Whole Numbers
In this unit, your child multiplies multi-digit whole numbers, like 213 × 32. They start with area models and partial products, then move to the usual written method, estimating first so they can tell whether a product makes sense. It follows decimal addition and subtraction, and the same place-value thinking leads into dividing whole numbers next.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Unit 4?
- Multiplying multi-digit whole numbers with area models, partial products, and the usual written method, and estimating to check. Learn more: Multiplying big numbers, like 213 × 32
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
Each apple tree in an orchard grows 30 apples. The orchard has 120 trees. How many apples do the trees grow?
- 36,000
- 3,600
- 150
How you can help
- Work out a real total together, like the seats in a theater with 28 rows of 24, or the eggs in 15 cartons of 12.
- Estimate a product before you solve by rounding: 213 × 32 is about 200 × 30. Ask whether the exact answer will be a bit more or a bit less.
- Count something on a walk or ride in groups, like windows in rows on a building. Ask your child to multiply rows by windows per row instead of counting one by one.
Where kids can get stuck
- Forgetting the placeholder zero when multiplying by the tens digit, so the second partial product is ten times too small.
- Misaligning the partial products, so tens sit under hundreds and the total comes out far off.
- Adding a carried digit before multiplying instead of after, so 7 × 4 with a carry of 2 becomes 42 instead of 30.
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
- factor
- A number that is multiplied by another number.
- product
- The answer to a multiplication problem.
- partial product
- Part of a multiplication answer, found by multiplying one place at a time.
- area model
- A rectangle split into parts to show multiplication or division.
- algorithm
- A step-by-step method for solving a problem, like the usual way to multiply on paper.
- estimate
- A close guess found by rounding or using easy numbers.
- regroup
- To trade 10 of one place for 1 of the next place, or the reverse.
Ready to build your child’s confidence with multi-digit 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 Reveal Math Grade 5 Unit 4 cover?
Reveal Math Grade 5 Unit 4 covers this math standard. Each one links to what it means, sample questions, and teaching strategies.
- 5.NBT.B.5: Fluently multiply larger numbers, like 213 × 32.
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.