Ten ones make a ten: 2nd grade math lesson

What this lesson shows

Fixes a mistake

54 + 39 is 93, not 813. The 13 ones are 1 ten and 3 ones.

The worked example

The lesson works this one step by step: 54 + 39 = □. Then your kid tries one like it on paper.

The steps

Add the tens
Add the ones
Trade 10 ones for a ten
One digit in each place

Helping at home

Each place holds one digit. When the ones make 10 or more, trade 10 of them for a new ten, then write the tens and the ones left.

If your kid gets stuck

Each place holds one digit.

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 2.NBT.B.5
Fluently add and subtract within 100 using strategies based on place value, properties of operations, and/or the relationship between addition and subtraction.

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

Alabama MA19.2.10
Alaska 2.NBT.5
Arizona 2.NBT.B.5
Arkansas 2.CAR.2
California 2.NBT.B.5
Colorado 2.NBT.B.5
Connecticut 2.NBT.B.5
Delaware 2.NBT.B.5
District of Columbia 2.NBT.B.5
Florida MA.2.NSO.2.3
Georgia 2.NR.2.3, 2.NR.2.4
Hawaii 2.NBT.B.5
Idaho 2.NBT.B.5
Illinois 2.NBT.B.5
Indiana 2.CA.3
Iowa 2.NBT.B.5
Kansas 2.NBT.5
Kentucky KY.2.NBT.5
Louisiana 2.NBT.B.5
Maine 2.NBT.B.5
Maryland 2.NOS.B.6.c, 2.NOS.C.8.a, 2.NOS.C.8.b
Massachusetts 2.NBT.B.5
Michigan 2.NBT.B.5
Minnesota 2.1.2.3, 2.1.2.4
Mississippi 2.NBT.5
Missouri 2.NBT.B.6, 2.NBT.B.9
Montana MT.1.NBT.6, MT.2.NBT.5
Nebraska 1.N.4.g, 2.N.4.b
Nevada 2.NBT.B.5
New Hampshire 2.NBT.B.5
New Jersey 2.NBT.B.5
New Mexico 2.NBT.B.5
New York NY-2.NBT.5
North Carolina NC.2.NBT.5.a, NC.2.NBT.5.c
North Dakota 2.NO.NBT.3, 2.NO.NBT.4, 2.AR.OA.2
Ohio 2.NBT.5
Oklahoma 2.N.2.4
Oregon 2.NBT.B.5
Pennsylvania CC.2.1.2.B.3
Rhode Island 2.NBT.B.5
South Carolina 2.PAFR.1.4, 2.PAFR.1.1
South Dakota 2.NBT.B.5
Tennessee 1.NBT.C.7, 2.NBT.B.5, 2.OA.B.2
Texas 111.4.b.4.B
Utah 2.NBT.5
Vermont 2.NBT.B.5
Virginia 2.CE.1a, 2.CE.1b
Washington 2.NBT.B.5
West Virginia M.2.10
Wisconsin M.2.NBT.B.5
Wyoming 2.NBT.5

Ten ones make a ten