Turn the array: 3rd grade math lesson

What this lesson shows

4 × 6 turned is 6 × 4. Same dots, same product.

The worked example

The lesson works this one step by step: 4 × 6. Then your kid tries one like it on paper.

The steps

Draw the rows
Turn the array
Same dots, same product

Helping at home

Draw the array as rows of dots, then draw it again turned, rows becoming columns. Count both: the same dots give the same product. Say the commutative property in your own words.

If your kid gets stuck

Draw the rows first, then turn them.

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.)
Common Core 3.OA.C.7
Fluently multiply and divide within 100, using strategies such as the relationship between multiplication and division (e.g., knowing that 8 × 5 = 40, one knows 40 ÷ 5 = 8) or properties of operations. By the end of Grade 3, know from memory all products of two one-digit numbers.

Matches a standard in all 50 states and DCSee each state's code

Alabama MA19.3.5, MA19.3.7a, MA19.3.7b
Alaska 3.OA.5, 3.MD.9.c, 3.OA.7
Arizona 3.OA.B.5, 3.OA.C.7 *
Arkansas 3.CAR.2, 3.CAR.3
California 3.OA.B.5, 3.OA.C.7
Colorado 3.OA.B.5, 3.OA.C.7
Connecticut 3.OA.B.5, 3.OA.C.7
Delaware 3.OA.B.5, 3.OA.C.7
District of Columbia 3.OA.B.5, 3.OA.C.7
Florida MA.3.NSO.2.4, MA.3.AR.1.1
Georgia 3.PAR.3.3, 3.PAR.3.2
Hawaii 3.OA.B.5, 3.OA.C.7
Idaho 3.OA.B.5, 3.OA.C.7.b, 3.OA.C.7.a
Illinois 3.OA.B.5, 3.OA.C.7
Indiana 4.CA.3, 3.CA.5, 3.CA.6, 3.CA.3
Iowa 3.OA.B.5, 3.OA.C.7
Kansas 3.OA.5, 3.OA.7
Kentucky KY.3.OA.5, KY.3.OA.7
Louisiana 3.OA.B.5, 3.OA.C.7
Maine 3.OA.B.5, 3.OA.C.7
Maryland 3.NOS.C.4, 3.NOS.E.9.a, 3.NOS.E.9.b, 3.NOS.E.9.c, 4.NOS.C.7.a, 4.NOS.C.7.c, 3.NOS.E.9.d, 4.NOS.C.7.b
Massachusetts 3.OA.B.5, 3.OA.C.7
Michigan 3.OA.B.5, 3.OA.C.7
Minnesota 3.1.2.5, 5.2.2.1, 4.1.1.1
Mississippi 3.OA.5, 3.OA.7
Missouri 3.RA.B.6, 3.RA.C.7, 3.RA.C.8
Montana MT.3.OA.5, MT.3.MD.7.c, MT.3.OA.7
Nebraska 3.A.1.e, 3.A.1.g
Nevada 3.OA.B.5, 3.OA.C.7
New Hampshire 3.OA.B.5, 3.OA.C.7
New Jersey 3.OA.B.5, 3.OA.C.7
New Mexico 3.OA.B.5, 3.OA.C.7
New York NY-3.OA.5, NY-3.OA.7.a, NY-3.OA.7.b
North Carolina NC.3.OA.1.b, NC.3.OA.2.b, NC.3.OA.7.a, NC.3.OA.7.b
North Dakota 3.AR.OA.1, 3.AR.OA.2, 4.AR.OA.2, 5.AR.OA.1, 4.AR.OA.1
Ohio 3.OA.5, 3.MD.7.c, 3.OA.7
Oklahoma 3.N.2.2, 3.N.2.8, 3.A.2.2, 5.A.2.1, 4.N.2.1
Oregon 3.OA.B.5, 3.OA.C.7
Pennsylvania CC.2.2.3.A.2, CC.2.2.3.A.3
Rhode Island 3.OA.B.5, 4.OA.A.3.a, 3.OA.C.7
South Carolina 3.PAFR.1.3
South Dakota 3.OA.B.5, 3.OA.C.7.a, 3.OA.C.7.b
Tennessee 3.OA.B.5, 3.OA.C.7, 3.MD.C.7.c
Texas 111.5.b.4.F, 111.5.b.4.G
Utah 3.OA.5, 3.OA.7.b, 3.OA.7.a
Vermont 3.OA.B.5, 3.OA.C.7
Virginia 3.CE.2c, 3.CE.2d, 3.CE.2f
Washington 3.OA.B.5, 3.OA.C.7
West Virginia M.3.5, M.3.7
Wisconsin M.3.OA.C.6, M.3.OA.B.4, M.4.OA.D.6
Wyoming 3.OA.7, 3.MD.7c, 3.MDP.7.C

Turn the array