Recently I taught my son (grade 2) how to do subtraction of large numbers with borrowing. I am a high school math teacher, so I thought that teaching this subject would be a piece of cake. However, I didn't realize that I would have to be this creative in order to actually get through to my son. Anyway, my method worked like a charm, so I'm posting it. It's pretty basic, and I'm sure it has been widely used by good teachers (that really understand how to teach kids math), but in case you haven't thought of this method, here it is.