This product is designed to be used as a set of problem cards in a Montessori or home school environment, but could also be copied as a worksheet or handout. It provides students with experience adding and subtracting simple equations in both horizontal and vertical formats. There are 20 cards, with six equations linked together. The final answer is given, so that children can check to see that they arrived at the correct answer. If they get a different answer, they can then go back and chec