number squares...

So it looks like kids aren't learning subtraction the way that we used to anymore. I was helping a student at 826 tonight with some math homework and she couldn't do a particular subtraction in her head so I suggested she write it down and do it by hand. But she didn't know how to do that...apparently CPS now teaches subtraction with a 10x10 grid that they call a number square. If you want to do 100-13, just move up one and left three and there's your answer. Great if you need to subtract things under 100 and you always have one of these fancy little squares around, but seriously if you don't, you have *no clue* how to do subtraction. I see this as a "bad thing."