What math should a 3rd grader know? A parent checklist

Quick answer

By the end of 3rd grade, children should know all products of two one-digit numbers from memory and multiply and divide fluently within 100. They also add and subtract fluently within 1,000, round to the nearest 10 or 100, solve two-step word problems, and understand fractions as numbers on a number line. Measurement adds time to the minute, area and perimeter.

3rd grade is the year of multiplication, division and fractions. It's a big step: children move from adding and subtracting to thinking in equal groups, and fractions become real numbers. Below is a parent-friendly checklist of what 3rd graders are expected to know by the end of the year, based on the Common Core State Standards used by most U.S. states (your state or school may differ). Each item lists its standard code so you can match it to report cards.

Multiplication and division (operations and algebraic thinking)

• Understand multiplication as equal groups: 5 × 7 is 5 groups of 7 (3.OA.A.1).
• Understand division two ways: 56 ÷ 8 can mean 56 shared into 8 groups, or 56 put into groups of 8 (3.OA.A.2).
• Solve multiplication and division word problems within 100 about equal groups, arrays and measurements (3.OA.A.3).
• Find unknown numbers in equations like 8 × ? = 48 (3.OA.A.4), and see division as a missing-factor problem: 32 ÷ 8 asks “8 times what is 32?” (3.OA.B.6).
• Use properties as shortcuts: 6 × 4 = 4 × 6, and 8 × 7 = 8 × 5 + 8 × 2 = 40 + 16 = 56 (3.OA.B.5).
• Multiply and divide fluently within 100, and know all products of two one-digit numbers from memory by the end of the year (3.OA.C.7).
• Solve two-step word problems with all four operations, write an equation with a letter for the unknown, and check that the answer is reasonable by estimating (3.OA.D.8).
• Spot and explain patterns in the addition and multiplication tables, like “4 times any number is even” (3.OA.D.9).

Memorizing the 11 and 12 times tables is common practice in many schools, but it isn't a Common Core requirement. Our guides to teaching multiplication, teaching division and learning times tables fast show how to get there.

Place value: rounding, adding and subtracting to 1,000

• Round whole numbers to the nearest 10 or 100: 47 rounds to 50, and 263 rounds to 300 (3.NBT.A.1).
• Add and subtract fluently within 1,000, using place-value strategies or a written method (3.NBT.A.2).
• Multiply one-digit numbers by multiples of 10: 9 × 80 = 720, because 9 × 8 tens = 72 tens (3.NBT.A.3).

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Fractions as numbers

3rd-grade fractions use denominators (bottom numbers) of 2, 3, 4, 6 and 8. Children should:

• Understand unit fractions: 1/4 is one part when a whole is split into 4 equal parts, and 3/4 is three of those parts (3.NF.A.1).
• Place fractions on a number line by splitting the space from 0 to 1 into equal parts (3.NF.A.2).
• Recognize simple equivalent fractions, such as 1/2 = 2/4 and 4/6 = 2/3, and explain why with a picture (3.NF.A.3.a, 3.NF.A.3.b).
• Write whole numbers as fractions: 3 = 3/1, and 4/4 = 1 (3.NF.A.3.c).
• Compare fractions with the same denominator (3/8 < 5/8) or the same numerator (1/3 > 1/6), remembering that comparisons only work when both fractions refer to the same whole (3.NF.A.3.d).

A classic mix-up: thinking 1/6 is bigger than 1/3 because 6 is bigger than 3. Cut two same-size sandwiches, one into 3 equal pieces and one into 6, and let your child see which piece is bigger.

Measurement and data: time, volume, graphs, area and perimeter

• Tell time to the nearest minute and solve elapsed-time problems in minutes, such as “Practice starts at 3:45 and lasts 50 minutes. When does it end?” (4:35) (3.MD.A.1).
• Measure and estimate liquid volume and mass in liters, grams and kilograms, and solve one-step word problems with them (3.MD.A.2).
• Draw and read scaled picture graphs and bar graphs, where one square might stand for 5 pets, and answer “how many more” and “how many less” questions (3.MD.B.3).
• Measure lengths to the nearest half or quarter inch and show the data on a line plot (3.MD.B.4).
• Understand area as the number of unit squares that cover a shape, and measure it by counting squares (3.MD.C.5, 3.MD.C.6).
• Connect area to multiplication: multiply side lengths to find a rectangle's area, and split L-shapes into rectangles and add their areas (3.MD.C.7).
• Solve perimeter problems, including finding a missing side and finding rectangles with the same perimeter but different areas (3.MD.D.8).

The same rectangle's perimeter is the distance around it: 3 + 5 + 3 + 5 = 16 units. Area counts the tiles inside; perimeter measures the fence around the outside.

Geometry: shapes and quadrilaterals

• Sort shapes by shared features: rhombuses, rectangles and squares all have four sides, so they are all quadrilaterals. Children also draw quadrilaterals that are none of these (3.G.A.1).
• Split shapes into parts with equal area and name each part as a unit fraction: each of 4 equal parts is 1/4 of the shape (3.G.A.2).

Signs your child may need extra help

If any of these patterns last for several weeks, have a friendly chat with the teacher:

• Late in the year, still skip-counting from the start for most facts (7, 14, 21… to find 7 × 8). Skip counting is a fine early strategy, but by the end of 3rd grade facts should be coming from memory.
• Not seeing that 4 × 6 = 24 and 24 ÷ 6 = 4 are connected.
• Thinking 1/8 is bigger than 1/4 because 8 is bigger than 4.
• Mixing up area and perimeter.
• Frequent regrouping slips in three-digit subtraction, like 503 − 278.
• Not knowing which operation a word problem needs, even after drawing it.

All of these are common and fixable. Our guide for when a child struggles with math has practical next steps.

5–10 minute math ideas for home

• Table of the week: skip-count one times table, then quiz it in the car. Mix in the division facts too: 6 × 7 = 42, so 42 ÷ 7 = 6.
• Array hunt: egg cartons, muffin tins and window panes. Name the multiplication and division facts you see.
• Kitchen fractions: use 1/2-cup and 1/4-cup measures. How many quarter cups fill a half cup?
• Elapsed time: “We leave at 4:10 and the drive takes 25 minutes. When do we arrive?” (4:35)
• Sticky-note area: cover a book with sticky notes, count them, then check by multiplying rows × columns.
• Card products: flip two cards (ace to 9) and say the product. Keep a multiplication chart handy for checking.

Want more? Try our times tables worksheets and see math facts fluency by grade for realistic targets.

How 3rd grade sets up 4th grade

• Times tables become the engine for multiplying bigger numbers (four digits by one digit, two digits by two digits) and dividing up to four-digit numbers, with remainders.
• Fractions grow into equivalent fractions with more denominators, adding and subtracting fractions with like denominators, and decimals to hundredths.
• Area and perimeter turn into formulas for rectangles.
• Rounding extends to any place, with numbers up to 1,000,000.

See what's ahead in the 4th grade math checklist, or review the 2nd grade checklist if some foundations need a refresh.

Can my child do this? Quick self-check and practice

Use these as a relaxed check-in near the end of the year. Quick, confident answers mean a skill is on track; any hesitation shows you what to practice next.

3rd grade practice (with answers)

1. 7 × 8 = ?
2. 54 ÷ 6 = ?
3. 6 × ? = 42
4. 9 × 80 = ?
5. Round 347 to the nearest hundred
6. 615 − 287 = ?
7. Which is greater: 1/3 or 1/6?
8. How many fourths equal 1/2?
9. Area of a rectangle 4 units by 7 units?
10. Perimeter of that rectangle?
11. A show starts at 2:35 and lasts 40 minutes. When does it end?
12. Sam has 3 packs of 8 cards and gives away 5. How many are left?

Show answers

Frequently asked questions

What math do 3rd graders learn?

3rd grade centers on multiplication and division within 100, fractions and area. Children also round to the nearest 10 or 100, add and subtract within 1,000, solve two-step word problems, tell time to the minute, measure liquid volume and mass, read scaled bar graphs, find perimeter, and sort shapes into categories like quadrilaterals.

Do 3rd graders need to know their times tables?

Yes. Common Core standard 3.OA.C.7 says that by the end of 3rd grade, children should know from memory all products of two one-digit numbers, from 0 × 0 up to 9 × 9, and multiply and divide fluently within 100. Many schools also practice the 11 and 12 times tables, but those aren't part of the Common Core.

What fractions do 3rd graders learn?

3rd graders work with fractions that have denominators 2, 3, 4, 6 and 8. They learn that 1/4 is one of four equal parts, place fractions on a number line, find simple equivalent fractions like 1/2 = 2/4, and compare fractions with the same top or bottom number. Adding fractions comes in 4th grade.

Do 3rd graders learn long division?

No. 3rd graders divide within 100, mostly by using multiplication facts (3.OA.C.7). Dividing bigger numbers, with remainders, comes in 4th grade, and fluency with the standard long-division algorithm is a 6th-grade standard, though many schools introduce it in 4th or 5th grade.

What is the difference between area and perimeter?

Area is how much flat space a shape covers, measured in square units: a 3-by-5 rectangle covers 15 unit squares. Perimeter is the distance around the outside, measured in units: 3 + 5 + 3 + 5 = 16. 3rd graders learn both, and even find rectangles with the same perimeter but different areas.

How can I help my 3rd grader with math at home?

Keep it short and regular: five to ten minutes on most days. Practice one times table at a time with skip counting and games, ask real-life questions about time and money, and cut snacks into fractions. When your child gets stuck on a word problem, ask them to draw a picture before calculating.

Sources

• Common Core State Standards for Mathematics — CCSSI
• Common Core State Standards: Grade 3, Operations & Algebraic Thinking — CCSSI
• Common Core State Standards: Grade 3, Number & Operations in Base Ten — CCSSI
• Common Core State Standards: Grade 3, Number & Operations—Fractions — CCSSI
• Common Core State Standards: Grade 3, Measurement & Data — CCSSI
• Common Core State Standards: Grade 3, Geometry — CCSSI

Written by The Mathing Team for parents and teachers. Grade expectations follow the Common Core State Standards for Mathematics; your state or school may sequence skills a little differently.