Go Math! Grade 2, Chapter 1: Number Concepts
In this unit, the year begins with number ideas your child will use every day. They sort numbers into odd and even, write even numbers as doubles, and skip-count by 5s and 10s. They also read and write two-digit numbers in words and in expanded form, like 40 + 7. Next, these ideas stretch to numbers up to 1,000.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Chapter 1?
- Telling odd from even by pairing objects and writing even numbers as the sum of two equal addends, like 10 = 5 + 5. Learn more: Odd and even numbers
- Skip-counting by 5s and 10s from different starting numbers and spotting the pattern in each count. Learn more about counting within 1,000: Counting within 1,000 · Learn more about skip-counting by 5s, 10s, and 100s
- Reading and writing two-digit numbers in words, as numerals, and in expanded form, such as 40 + 7. Learn more: Reading and writing numbers to 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
Is 16 an even or odd number?
- Even
- Odd
- Neither
How you can help
- Count stairs or socks by 2s, and ask whether the last number you landed on is odd or even. Then try a pile with one sock missing.
- Skip-count by 5s and 10s on a walk or ride, sometimes starting at 3 or 15, and listen together for the pattern in the ones digit.
- Write a number like 47 and ask your child to say it three ways: as forty-seven, as 4 tens 7 ones, and as 40 + 7.
Where kids can get stuck
- Judging odd or even by size, thinking 18 must be odd because it is big.
- Counting by 10s only from round numbers, unsure how to go 13, 23, 33.
- Writing forty-seven as 407 because that is how it sounds.
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
- odd
- A number that can't be split into pairs without one left over, like 7.
- even
- A number that can be split into pairs with none left over, like 8.
- equal addends
- Numbers being added that are the same, like 5 + 5.
- pair
- A group of two.
- skip-count
- Counting by a number other than one, like 5, 10, 15, 20.
- pattern
- Something that repeats or changes the same way each time, like 5, 10, 15, 20.
- expanded form
- A number written as the sum of its parts, like 400 + 30 + 6 for 436.
- digit
- One of the symbols 0 through 9 that we use to write numbers.
Ready to build your child’s confidence with number sense?
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 2 Chapter 1 cover?
Go Math! Grade 2 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.