What this lesson shows
Fixes a mistake
Counting 9 + 5 dot by dot is slow. 10 + 5 is 15, so 9 + 5 is 14.
The worked example
The lesson works this one step by step: 9 + 5 = □. Then your kid tries one like it on paper.
The steps
- Counting every dot is slow
- Find a 10 nearby
- Use the fact you know
- Adjust
Helping at home
Look for a 10 nearby. 9 is 1 less than 10, so 9 + 5 is 1 less than 10 + 5. Use the fact you know, then adjust.
If your kid gets stuck
Is one number close to 10?
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.OA.B.2
Fluently add and subtract within 20 using mental strategies. By end of Grade 2, know from memory all sums of two one-digit numbers.
Matches a standard in all 50 states and DCSee each state's code
- Alabama MA19.2.2a
- Alaska 2.OA.2
- Arizona 2.OA.B.2
- Arkansas 2.CAR.1
- California 2.OA.B.2
- Colorado 2.OA.B.2
- Connecticut 2.OA.B.2
- Delaware 2.OA.B.2
- District of Columbia 2.OA.B.2
- Florida MA.2.NSO.2.1
- Georgia 2.NR.2.1
- Hawaii 2.OA.B.2
- Idaho 2.OA.B.2
- Illinois 2.OA.B.2
- Indiana 1.CA.1
- Iowa 2.OA.B.2
- Kansas 2.OA.2
- Kentucky KY.2.OA.2
- Louisiana 2.OA.B.2
- Maine 2.OA.B.2
- Maryland 2.NOS.B.6.a, 2.NOS.B.6.b
- Massachusetts 2.OA.B.2
- Michigan 2.OA.B.2
- Minnesota 2.1.2.1, 2.1.2.2
- Mississippi 2.OA.2
- Missouri 2.RA.A.1
- Montana MT.2.OA.2
- Nebraska 2.N.4.a
- Nevada 2.OA.B.2
- New Hampshire 2.OA.B.2
- New Jersey 2.OA.B.2
- New Mexico 2.OA.B.2
- New York NY-2.OA.2.a, NY-2.OA.2.b
- North Carolina NC.2.OA.2
- North Dakota 2.AR.OA.1
- Ohio 2.OA.2
- Oklahoma 2.N.2.1, 2.N.2.2
- Oregon 2.OA.B.2
- Pennsylvania CC.2.2.2.A.2
- Rhode Island 2.OA.B.2
- South Carolina 2.PAFR.1.5
- South Dakota 2.OA.B.2.a, 2.OA.B.2.b
- Tennessee 2.OA.B.2
- Texas 111.4.b.4.A
- Utah 2.OA.2.a, 2.OA.2.b
- Vermont 2.OA.B.2
- Virginia 2.CE.1d, 2.CE.1e, 2.CE.1h
- Washington 2.OA.B.2
- West Virginia M.2.2
- Wisconsin M.2.OA.B.2
- Wyoming 2.OA.2