How counting tells you how many
In kindergarten, children learn that each object gets one number, that the last number counted tells how many, and that each next number is one more.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
Try these with your child
These are real questions from our kindergarten 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
You count 3 bears. How many bears are there?
- 2
- 3
- 4
Why this matters
These three ideas are what let your child trust their own count. With them, your child can compare groups, add by counting on, and know that 12 and one more is 13 without starting again. They also prepare for 1st grade, where 13 is seen as one ten and three ones, and for adding and subtracting within 20, where careful counting keeps the answers right.
Where kids can get stuck
- Touching each of 15 toys but counting some twice, so the total changes every time they count.
- Starting again from 1 when asked how many, right after counting 12 cars correctly.
- Recounting all 9 objects after one more is added, instead of knowing the new total is 10.
How you can help
- Count out 15 pieces of cereal together, then spread them in a circle and ask whether there are still 15 before counting to check.
- Count the people waiting in a line at the store, then ask how many there would be if one more person joined, without counting again.
- Ask your child to count the steps between two rooms, then walk them back and count again to show that the total stays the same.
If it’s helpful, you can watch the kid-friendly video below, or sign up for free, adaptive practice in Bobby's Math Club.
Kid-friendly explanation
Questions parents ask
Why does my child need to know that rearranging objects doesn't change the total?
Understanding that a group of 12 is still 12 when it is spread out or bunched together shows that your child trusts counting over appearance. That trust is essential for comparing groups and adding. It also prepares them for seeing that numbers can be split and rearranged, which they use in decomposing numbers and adding in different orders.
My child counts well to 10 but makes mistakes with larger groups. Why?
Larger groups are harder to keep track of, and the teen number words are less familiar. Children may lose their place or count an object twice. Encourage your child to move each object into a new pile as they count it, or to line objects up first. Those habits keep the count accurate as numbers grow.
How is this different from what my child learned in Pre-K?
The ideas are the same, but kindergarten works with groups up to 20 and expects your child to use the ideas more confidently. Knowing that each number is one more becomes the basis for counting on to add, and knowing the last number is the total lets your child compare groups and solve problems.
Make learning math fun
Bobby's Math Club turns kindergarten math practice into something fun to do together.
- Unlimited practice, completely free
- A few minutes a day, at just the right level
- Level-ups, badges, and a cheer for every win
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.
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Join the clubNote for teachers: This skill is covered by Common Core math standard K.CC.B.4: “Understand the relationship between numbers and quantities; connect counting to cardinality. a. When counting objects, say the number names in the standard order, pairing each object with one and only one number name and each number name with one and only one object. b. Understand that the last number name said tells the number of objects counted. The number of objects is the same regardless of their arrangement or the order in which they were counted. c. Understand that each successive number name refers to a quantity that is one larger.” Learn how Bobby's Math Club can help your students grow. (Common Core K.CC.4)