Illustrative Mathematics Kindergarten, Unit 4: Understanding Addition and Subtraction
In this unit, your child makes sense of adding and subtracting through stories. Kindergartners act out situations where things are put together or taken apart, show them with drawings or fingers, break a number into two parts, and become quick with facts within 5. It uses the counting from earlier units, and the next unit looks more closely at all the ways to build numbers up to 10.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Unit 4?
- Acting out adding and subtracting with objects, fingers, and drawings, and connecting them to equations like 4 - 1 = 3. Learn more about showing addition in many ways: Showing addition in many ways · Learn more about showing subtraction in many ways
- Solving story problems within 10 by acting them out or drawing what happens to find how many in all or how many are left. Learn more: Adding and subtracting story problems within 10
- Breaking a number into two parts, such as 5 as 3 and 2, and showing the parts with objects or a drawing. Learn more: Splitting numbers up to 10 into two parts
- Becoming quick with adding and subtracting facts within 5, such as 2 + 3 = 5 and 4 - 2 = 2. Learn more about adding fluently within 5: Adding fluently within 5 · Learn more about subtracting fluently within 5
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
Start at 7 and hop back 2. Where do you land?
- 2
- 9
- 5
How you can help
- Turn snack time into a story, such as '6 crackers on your plate and you eat 2,' and let your child act it out before answering.
- Split 5 stuffed animals into two groups, such as 3 on the bed and 2 on the floor, and then find another way to split them.
- Toss a soft ball back and forth and call out a fact within 5 with each catch, such as '3 plus 1' or '4 minus 2.'
Where kids can get stuck
- Drawing a take-away story as two separate groups instead of crossing out the ones that leave.
- Losing track of a story partway and adding when some things were taken away.
- Counting every fact from 1, even 1 + 1, so small sums are slow.
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
- add
- To put groups together to find how many in all.
- subtract
- To take some away from a group and find how many are left.
- equation
- A math sentence with an equal sign, like 3 + 2 = 5.
- part
- One of the smaller amounts a number can be broken into.
- whole
- The full amount that the parts make together.
- in all
- How many there are altogether after groups are put together.
- left
- How many remain after some are taken away.
Want to help your child master addition and subtraction stories?
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 Illustrative Mathematics Kindergarten Unit 4 cover?
Illustrative Mathematics Kindergarten Unit 4 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.