1st Grade Math · Parent guide
What Math Should a 1st Grader Know?
Complete Parent Guide
By the end of 1st grade, your child should add and subtract within 20 (with facts within 10 coming quickly), understand that a number like 34 is 3 tens and 4 ones, count and write numbers to 120, measure length by laying units end to end, tell time to the hour and half hour, and describe shapes by their sides and corners. Those are the four focus areas the Common Core math standards set for grade 1. Below you will find each area in plain English, real examples of 1st grade problems, the signs that a child is falling behind, and quick activities you can do at home.
Reviewed against the Common Core standards.
What 1st Graders Learn in Math, by Domain
These are the Common Core State Standards for Grade 1 math, grouped by domain and put into plain English. Many states use them as written or in an adapted version, so your school's wording may differ slightly. The code after each skill is the standard it comes from, and each domain links to the full text on the Common Core site. Read the official Grade 1 introduction.
Operations & Algebraic Thinking
Common Core 1.OA- Solve word problems within 20 where the missing number can be anywhere: the start, the change or the total (1.OA.1)
- Add three numbers whose total is 20 or less, such as 4 + 7 + 6 (1.OA.2)
- Use strategies like counting on, making ten (8 + 6 = 8 + 2 + 4) and using a known fact to find a new one (1.OA.6)
- Be fluent with addition and subtraction within 10 by the end of the year (1.OA.6)
- Understand that the equal sign means "the same as" and decide whether 7 = 8 - 1 or 4 + 1 = 5 + 2 is true (1.OA.7)
Number & Operations in Base Ten
Common Core 1.NBT- Count to 120 starting from any number, and read and write those numbers (1.NBT.1)
- Know that the two digits of a number like 34 mean 3 tens and 4 ones, and that 11 to 19 are a ten and some ones (1.NBT.2)
- Compare two-digit numbers with >, = and < (1.NBT.3)
- Find 10 more or 10 less than a two-digit number in their head, without counting (1.NBT.5)
- Add within 100 using tens and ones, such as 46 + 30 or 38 + 5 (1.NBT.4)
Measurement & Data
Common Core 1.MD- Put three objects in order by length, and compare two lengths using a third object (1.MD.1)
- Measure a length by laying copies of a shorter object end to end with no gaps (1.MD.2)
- Tell and write time in hours and half hours on analog and digital clocks (1.MD.3)
- Sort data into up to three groups and answer "how many more?" questions about it (1.MD.4)
Geometry
Common Core 1.G- Tell defining features (a triangle is closed with three sides) from features that do not matter (color, size, which way it is turned) (1.G.1)
- Put shapes together to make new shapes, such as two triangles into a rectangle (1.G.2)
- Split circles and rectangles into halves and fourths (quarters), and know that more equal shares means smaller shares (1.G.3)
What 1st Grade Math Problems Look Like
Original practice problems written to match the standards above, with the answer and the thinking we would hope to hear.
Missing number word problem (1.OA.1)
Maya had 8 stickers. Her brother gave her some more. Now she has 13. How many stickers did her brother give her?
Answer: 5. A strong 1st grader counts on from 8 to 13, or thinks "8 + 2 is 10, and 3 more is 13, so 2 + 3 = 5."
True or false? (1.OA.7)
Which of these are true? 6 = 6. 7 = 8 - 1. 4 + 1 = 5 + 2.
Answer: The first two are true. 4 + 1 = 5 + 2 is false, because 5 is not the same as 7. Children who think the equal sign means "write the answer next" often get this wrong.
10 more, 10 less (1.NBT.5)
What number is 10 more than 47? What number is 10 less than 47?
Answer: 57 and 37. The tens digit changes and the ones digit stays the same, and your child should know this without counting by ones.
Time (1.MD.3)
The short hand is halfway between the 3 and the 4. The long hand points to the 6. What time is it?
Answer: 3:30, or half past three.
Signs Your 1st Grader May Be Behind in Math
Every child moves at a different pace, and many of these are normal in the fall. If you still see them in the spring of 1st grade, talk to the teacher:
- !Counts every object from 1 to solve 8 + 3, instead of starting at 8 and counting on 9, 10, 11
- !Cannot say how many tens and ones are in 34, or thinks 34 and 43 are the same amount
- !Reads the equal sign as "the answer goes here," so 8 = 8 or 5 = 2 + 3 looks wrong to them
- !Needs to count by ones to find 10 more than 46
- !Still working out sums like 6 + 4 or 9 - 3 slowly by the end of the year, even though the standards expect facts within 10 to be fluent
Short At-Home Activities (10 Minutes or Less)
Play "Make 10"
Deal ten cards from a deck (aces = 1, no face cards). Your child finds pairs that make 10: 7 and 3, 6 and 4. Making ten is the strategy the standards name for adding bigger numbers like 8 + 6.
Bundle a number of the day
Use straws or craft sticks with rubber bands. Pick a number like 34 and bundle 3 tens and leave 4 loose. Then ask "what is 10 more?" and add one bundle.
Ask "how many more?" at snack time
If you have 9 crackers and your child has 5, ask how many more you have. Comparing is one of the word problem types first graders find hardest.
Check the clock at the half hour
Twice a day, ask your child to read an analog clock at the hour or half hour. Point out where the short hand sits at 3:30: halfway, not on the 3.
Go on a shape hunt
Find triangles, rectangles and circles around the house. Ask "how do you know that is a triangle?" and listen for "three sides, closed," not "it looks like one."
Find Your Child's Exact Level
Not sure where your first grader stands? Our diagnostic checks the 1st grade skills above (adding and subtracting, tens and ones, time and shapes) and shows you which are solid and which need work, in about 10 minutes.
Start the DiagnosticQuestions Parents Ask
Should my 1st grader know addition facts by heart?
Not all of them yet. The Common Core standards ask for fluency with addition and subtraction within 10 by the end of 1st grade (1.OA.6), and for knowing all sums of two one-digit numbers from memory by the end of 2nd grade (2.OA.2). Facts like 8 + 6 can still be worked out with a strategy such as making ten in 1st grade.
My 1st grader still counts on fingers. Is that a problem?
Not at the start of the year. What you want to see by spring is a better strategy: starting from the bigger number and counting on, or making a ten. If your child still counts every finger from 1 for 6 + 3 near the end of 1st grade, practice counting on and the "Make 10" game.
How high should a 1st grader count?
To 120, starting from any number, not just from 1 (1.NBT.1). Your child should also be able to read and write the numbers in that range. Counting on from a number like 87 is harder than counting from 1, so practice both.
Do 1st graders learn fractions?
Only the idea, not the numbers. First graders split circles and rectangles into two and four equal parts and use the words halves, fourths and quarters (1.G.3). Writing fractions like 1/4 starts in 3rd grade.
How do I know if my 1st grader needs extra math help?
Look at the warning signs above in the spring, especially trouble with tens and ones and with facts within 10. Those two ideas carry straight into 2nd grade, where children add and subtract within 1000. A short diagnostic can show which skills are missing.