What this lesson shows
Fixes a mistake
52 − 27 is 25, not 35. Taking 2 from 7 turns the problem around. Trade a ten instead.
The worked example
The lesson works this one step by step: 52 − 27 = □. Then your kid tries one like it on paper.
The steps
- Never turn the ones around
- Trade a ten for 10 ones
- Take the ones, then the tens
Helping at home
The ones you take away come from the first number’s ones. When there are not enough, trade a ten for 10 ones; never turn the ones around.
If your kid gets stuck
Which ones come away from which?
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.
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