One Atta Time Flash Cards Distance Learning Create New Sheet Select a Worksheet > Version 1 Version 2 Version 3 Version 4 Version 5 Version 6 Version 7 Version 8 Version 9 Version 10 Grab 'em All Add and Subtract (Within 20) 1oa6 Add two numbers with sums up to 20.Subtract a number from another number and find the difference up to 20.Build speed and accuracy with basic addition and subtraction facts.