Reveal Math Grade 1, Unit 8: Tens and Ones
In this unit, your child looks closely at tens and ones. They learn that 10 ones make a ten, that numbers from 11 to 19 are a ten and some ones, and that a number like 80 is 8 tens and 0 ones. This builds on counting to 120 and leads into two-digit addition and subtraction.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Unit 8?
- Seeing a two-digit number as tens and ones, so 46 is 4 tens and 6 ones, 13 is a ten and 3 ones, and 80 is 8 tens. Learn more: Tens and ones in two-digit numbers
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
What number is 3 tens and 4 ones?
- 43
- 34
- 7
How you can help
- Bundle 10 straws with a rubber band and keep some loose. Show numbers like 13 and 31 and ask what is different.
- Count cereal pieces into small cups of 10 at snack time. Ask how many full cups and how many extra pieces, then name the number.
- Ask place value riddles on a walk: "I have 5 tens and 2 ones. What number am I?" Then let your child make one for you.
Where kids can get stuck
- Reading the 4 in 46 as 4 ones, so they show 46 with 4 straws and 6 straws.
- Writing 80 as 8, because the zero seems to mean nothing.
- Mixing up 13 and 31, putting the ten in the wrong place.
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
- tens
- Groups of ten. In 34, the 3 means 3 tens.
- ones
- Single units. In 34, the 4 means 4 ones.
- digit
- One of the symbols 0 to 9 used to write numbers.
- place value
- What a digit is worth because of where it sits, like the 5 in 52 meaning 50.
- tens digit
- The digit on the left in a two-digit number, telling how many tens.
- ones digit
- The digit on the right in a two-digit number, telling how many ones.
Want to help your child master tens and ones?
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 Reveal Math Grade 1 Unit 8 cover?
Reveal Math Grade 1 Unit 8 covers this math standard. Each one links to what it means, sample questions, and teaching strategies.
- 1.NBT.B.2: Understand that the two digits of a two-digit number represent amounts of tens and ones.
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.