Bridges in Mathematics Grade 1, Unit 3: Adding Subtracting Counting & Comparing
In this unit, first graders count well past 100, compare two-digit numbers, and decide whether equations, number sentences with an equal sign, are true or false. Story problems keep their adding and subtracting sharp. It builds on the tens and ones in teen numbers from the last unit, and leads into measuring length and splitting shapes into equal parts next.
By Robert “Bobby” BarnettMath teacher, parent, and founder of Bobby’s Math Club
What is my child learning in Unit 3?
- Solving adding and comparing stories within 20, like working out how many more shells one child has than another. Learn more: Adding and subtracting story problems within 20
- Learning that the equal sign means "the same amount as," so 8 = 5 + 3 and 4 + 2 = 3 + 3 are both true. Learn more: What the equal sign really means
- Counting forward from any number up to 120 and reading and writing those numbers, including the ones past 100. Learn more: Counting, reading, and writing numbers to 120
- Comparing two-digit numbers by checking the tens first and writing the result with greater than, equal to, or less than. Learn more: Comparing two-digit numbers with >, =, and <
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
- Count forward together from a number other than 1 while you wait in line, like starting at 87 and going to 103. Pay special attention to the jump from 99 to 100.
- Compare two numbers you see out and about, like house numbers on a walk or prices at the store, and ask which is greater. Ask how they knew by looking at the tens.
- Write a few number sentences on a sticky note, like 9 = 4 + 5 and 3 + 3 = 7, and ask your child to mark each one true or false, then fix the false ones.
Where kids can get stuck
- Deciding 29 is bigger than 41 because 9 is bigger than 1, looking at ones before tens.
- Calling 8 = 5 + 3 backwards or false because the answer comes first.
- Saying "68, 69, 60" at the end of a decade instead of moving on to 70.
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
- equal sign
- The symbol = that means "the same amount as."
- true
- An equation is true when both sides are the same amount.
- false
- An equation is false when the two sides are different amounts.
- greater than
- The symbol > means the first number is bigger, like 9 > 4.
- less than
- The symbol < means the first number is smaller, like 4 < 9.
- tens
- Groups of ten. In 34, there are 3 tens.
- ones
- Single things not in a group of ten. In 34, there are 4 ones.
- numeral
- The written symbol for a number, like 25.
Want to help your child master comparing numbers?
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 Bridges in Mathematics Grade 1 Unit 3 cover?
Bridges in Mathematics Grade 1 Unit 3 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.