Into Math Grade 1, Unit 2: Addition and Subtraction Strategies
In this unit, your child moves past counting by ones and learns strategies for facts within 20, such as doubles, making a ten, and turning subtraction into addition. It builds on last unit's meaning of adding and subtracting and prepares children for the next unit, where they work with equations and the equal sign.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Unit 2?
- Switching the order of numbers to add, knowing 2 + 8 and 8 + 2 give the same sum, the answer to an addition problem. Learn more: Adding in any order to make it easier
- Thinking of 14 - 6 as 6 plus what makes 14, so known addition facts help with subtraction. Learn more: Subtracting by finding the missing part
- Adding and subtracting within 20 with strategies like doubles, near doubles, and making a ten, and recalling facts within 10 quickly. Learn more about adding within 20: Adding within 20 · Learn more about subtracting within 20
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
If you know that 7 + 3 = 10, what is 3 + 7?
- 3
- 10
- 7
How you can help
- Play doubles with fingers: hold up 4 fingers on each hand and ask for the total. Then put up one more finger and ask about 4 + 5.
- Set out 9 cereal pieces and 6 more at snack time. Ask your child to move 1 piece over to make 10 and say the new fact, 10 + 5.
- Turn subtraction into a missing-part question while cleaning up: "We need 12 toys in the bin, and 8 are there. How many more go in?"
Where kids can get stuck
- Thinking 3 + 9 and 9 + 3 must have different answers, so solving both from scratch.
- Splitting the wrong number when making a ten, such as breaking 9 apart in 9 + 6 instead of the 6.
- Subtracting by counting back one at a time and losing count, instead of thinking of the matching addition fact.
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
- sum
- The answer when you add numbers together.
- turnaround fact
- The same addition fact with the numbers switched, like 3 + 4 and 4 + 3.
- doubles
- Facts that add a number to itself, like 6 + 6 = 12.
- near doubles
- Facts that are one more than a double, like 6 + 7 = 6 + 6 + 1.
- make a ten
- Break apart a number so one part fills a ten, like 8 + 5 = 8 + 2 + 3.
- related facts
- An addition fact and a subtraction fact that use the same three numbers.
- strategy
- A plan or shortcut for solving a problem.
Ready to build your child’s confidence with addition and subtraction facts?
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 Into Math Grade 1 Unit 2 cover?
Into Math Grade 1 Unit 2 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.