Scratch Addition, European Subtraction, and the better way to do Long Division

Professor Blaire Madore, an Assistant Professor of Mathematics at the State University of NY in Potsdam, visited the fourth grade today. He shared new ways to look at algorithms, including: scratch addition, European subtractions, and long division.

Students learned that a calculator used to refer to a person, using Charles Dickens' character, Bob Cratchit, as an example. That calculators used to add long pages of numbers, and scratch addition probably was the method they used.

Wondering how the Europeans do subtraction? Thinking to yourself what would be a better way to do long division? Ask your fourth grader!