We have found that the movable number line somehow helps "cement" addition and subtraction for my one DD. I just went to the Lakeshore Learning store and bought one with the pointer that you slide back and forth. My other DD just looks at the number line I printed and laminated for her. Once in a while you will see her actually "count on" and "count back". We have also spend time in Singapore Math with number bonds for addition and subtraction and did all the math families hands on for a while with the cubes. That also seemed to help. My one DD seems to be very visual. After that we now just use quicktables in ALEKS to drill for speed. (They love the games in ALEKS so much they forget they are drilling facts at the same time.)
