Go Math! Grade 3, Chapter 1: Addition and Subtraction Within 1000
In this unit, your child begins third grade by adding and subtracting numbers up to 1,000. They round to the nearest 10 or 100 to estimate, use place value to break numbers apart, and regroup when a column needs it. Two-step story problems put these skills to work. Graphs and data come next, using the same adding and subtracting.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Chapter 1?
- Solving two-step problems, such as finding how many seats are left after two groups arrive, and checking whether answers are reasonable. Learn more: Story problems with two steps
- Rounding to the nearest 10 or 100 and using compatible numbers, ones that are easy to add, to estimate sums and differences. Learn more: Rounding to the nearest 10 or 100
- Adding and subtracting with regrouping, and using strategies like counting up to subtract 298 from 405 (107). Learn more about adding within 1,000: Adding within 1,000 · Learn more about subtracting within 1,000
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
A bakery made 500 cookies. They sold 235 on Saturday and 190 on Sunday. How many are left?
- 75
- 85
- 175
How you can help
- Round prices on a receipt to the nearest ten to estimate the total, then check the exact amount together and see how close you were.
- Ask how many more points one team needs to reach 500 in a game where they have 365, and let your child explain their method (135).
- Ask your child to explain a mental math trick for 199 + 245, such as thinking 200 + 245 and then taking away 1 (444).
Where kids can get stuck
- Subtracting the smaller digit from the larger in each column, so 523 − 168 becomes 445 instead of 355.
- Rounding 349 to 400 by rounding to 350 first and then rounding again.
- Answering only the first question in a two-step problem and stopping there.
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
- round
- To change a number to a nearby number that is easier to use.
- estimate
- A number close to the exact answer that you find quickly.
- compatible numbers
- Numbers that are easy to add or subtract in your head, like 250 and 50.
- regroup
- To trade 10 ones for 1 ten, or 10 tens for 1 hundred, and back.
- sum
- The answer to an addition problem.
- difference
- The answer to a subtraction problem.
- place value
- The value of a digit because of where it is in a number.
- addend
- A number being added, like 6 and 8 in 6 + 8.
Ready to build your child’s confidence with adding and subtracting big numbers?
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.
Join the club
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 Go Math! Grade 3 Chapter 1 cover?
Go Math! Grade 3 Chapter 1 covers these math standards. Each one links to what it means, sample questions, and teaching strategies.
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.