Addition Addition can be thought of as finding the whole when the parts are known. Place value greatly simplifies finding the sum of two numbers. To be efficient in adding, we start with the sums of numbers 1 + 1 through 9 + 9. These are best … [Read more...] about Dr. Cotter on Addition and Subtraction Facts
subtraction
2018 Summer Game #13: On the Number Ten
It is one of those blazing hot, 90º summer days. No one wants to be outside but without air conditioning, inside isn’t much better. My boys’ solution to this dilemma is the nice, cool basement where the computer happens to reside. In my desire to get … [Read more...] about 2018 Summer Game #13: On the Number Ten
Dr. Cotter on Subtraction Approaches
There are at least eight different ways to subtract multi-digit numbers. Even though a person has learned one method, it is good to explore other methods to enhance understanding. If a child has an accurate and efficient method of subtraction, do … [Read more...] about Dr. Cotter on Subtraction Approaches
RS2 Level C, Lesson 53: Subtraction Puzzle
There’s been some chatter on the forum groups about RS2 Level C, Lesson 53 and Lesson 54 and the Worksheet 25. I thought this would be a dandy topic for this week’s blog. Here’s the worksheet in question. It’s asking the child to complete the … [Read more...] about RS2 Level C, Lesson 53: Subtraction Puzzle