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3rd grade math · Unit 1: Multiplication and division

Facts from facts you know

What this lesson shows

6 × 9 as 4 × 9 + 2 × 9, one array split in two.

The worked example

The lesson works this one step by step: 6 × 9. Then your kid tries one like it on paper.

The steps

  1. Draw the rows
  2. Split off 5 rows
  3. Work out each part
  4. Add the parts

Helping at home

Draw the groups as rows of dots, then cut off 5 rows: fives are easy. Write each part in parentheses, work out each one, and add the two answers. Add the parts; never multiply them.

If your kid gets stuck

Split off 5 groups first.

Watch it with Lux

With Lux, this lesson is a narrated video and a printed page your kid works on. Then Lux helps with the same math on their own worksheet, one question at a time.

See how Lux works

Standards

  • Common Core 3.OA.B.5
    Apply properties of operations as strategies to multiply and divide. Examples: If 6 × 4 = 24 is known, then 4 × 6 = 24 is also known. (Commutative property of multiplication.) 3 × 5 × 2 can be found by 3 × 5 = 15, then 15 × 2 = 30, or by 5 × 2 = 10, then 3 × 10 = 30. (Associative property of multiplication.) Knowing that 8 × 5 = 40 and 8 × 2 = 16, one can find 8 × 7 as 8 × (5 + 2) = (8 × 5) + (8 × 2) = 40 + 16 = 56. (Distributive property.)
Matches a standard in all 50 states and DCSee each state's code

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