Zearn Math Grade 1, Mission 1: Sums and Differences to 10
In this unit, your child works with sums and differences to 10, the answers to adding and subtracting. They solve story problems, count on and back, see how addition and subtraction connect, and learn what the equal sign means. This first unit lays the groundwork for the next one, where place value meets adding and subtracting within 20.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Mission 1?
- Solving put-together and take-apart stories within 10 by drawing, using objects, and writing number sentences. Learn more: Adding and subtracting story problems within 20
- Noticing that 6 + 3 and 3 + 6 give the same total, so switching the order can make adding easier. Learn more: Adding in any order to make it easier
- Treating 10 - 7 as a missing part, asking 7 plus what makes 10. Learn more: Subtracting by finding the missing part
- Counting on to add and counting back to subtract, like 5, then 6, 7 for 5 + 2. Learn more: Counting on and back to add and subtract
- Building quick, accurate recall of facts within 10, like all the pairs that make 10. Learn more about adding within 20: Adding within 20 · Learn more about subtracting within 20
- Deciding whether equations like 5 = 5 or 2 + 3 = 4 + 1 are true or false. Learn more: What the equal sign really means
- Finding the missing number in equations within 10, such as 3 + ? = 8. Learn more: Missing numbers, like 8 + ? = 11
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
I had some toy cars. My friend gave me 3 more cars. Now I have 8 cars in total. How many toy cars did I have at first?
- 3
- 5
- 8
How you can help
- Play make 10 with fingers: hold up some fingers and ask how many more make 10. Switch roles so your child quizzes you.
- Tell little stories at snack time with crackers: "You have 7 and eat 3. How many are left?" Ask your child to say the number sentence.
- Write a true or false puzzle on a sticky note, like 4 + 1 = 3 + 2, and ask your child to explain how they decided.
Where kids can get stuck
- Counting both groups from 1 every time, instead of counting on from the first group.
- Thinking 6 = 6 or 8 = 5 + 3 is wrong, because the answer comes first.
- Giving the whole instead of the missing part, answering 8 for 3 + ? = 8.
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.
- difference
- The answer when you subtract one number from another.
- equation
- A number sentence with an equal sign, like 6 + 2 = 8.
- equal sign (=)
- A symbol that means both sides show the same amount.
- count on
- Start at a number and keep counting up from there.
- count back
- Start at a number and count down, one at a time.
- missing part
- The number you add to one part to reach the whole.
- true
- An equation is true when both sides of the equal sign match.
- false
- An equation is false when the two sides of the equal sign do not match.
Want to help your child master sums to 10?
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 Zearn Math Grade 1 Mission 1 cover?
Zearn Math Grade 1 Mission 1 covers these math standards. Each one links to what it means, sample questions, and teaching strategies.
- 1.OA.A.1: Use addition and subtraction within 20 to solve word problems.
- 1.OA.B.3: Apply properties of operations as strategies.
- 1.OA.B.4: Understand subtraction as an unknown-addend problem.
- 1.OA.C.5: Relate counting to addition and subtraction.
- 1.OA.C.6: Add and subtract within 20.
- 1.OA.D.7: Understand the meaning of the equal sign.
- 1.OA.D.8: Determine the unknown whole number in an addition or subtraction equation.
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.