These column subtraction charts are essential for helping students that have a difficult time lining up numbers to solve equations. The columns provide a visual guide to help set up each question, as well as focus on each step as the problem is being calculated. It can then be completely erased, so it is fresh and ready for the next use. This eliminates stray lines and distracting marks that can cause confusion during the solving process. For this reason, this manipulative works best if it is la