Help students look for the difference. The attached is based on the idea behind Ten Frames and is intended to help with basic subtraction. To get one in the habit of looking for the gap. It helps early on when filling out pages of single-digit subtraction problems. One can learn to quickly identify numbers one and two digits apart. Helps later on when faced with problems like: calculating: 201 - 199 = ? or, 201 - 6 = ? Same skill. Mind the gap. 'See' the values on a number line. Then decide