Becoming comfortable with two-digit and three-digit numbers is an important skill. Becoming comfortable with two-digit and three-digit numbers is an important skill in second grade. Your child will ...

Addition involves finding the total of two or more numbers or amounts. There are different things you can use to help you add. You can use number lines, place value charts and place value counters.

Column addition is a way of adding numbers together. It's helpful when you're adding two-digit or three-digit numbers together. When you do column addition, you lay out the numbers you are adding ...

Karen C. Fuson, Diana Wearne, James C. Hiebert, Hanlie G. Murray, Pieter G. Human, Alwyn I. Olivier, Thomas P. Carpenter and Elizabeth Fennema Researchers from 4 projects with a problem-solving ...