Subtract within 1000 using various representations, strategies, and algorithms. Warm up with a Mystery Math Mistake to find a mistake made in using an algorithm for addition and subtraction. Subtract ...

Fractions, often perceived as daunting, become manageable with the right approach. Addition and subtraction require finding a common denominator, while multiplication involves directly multiplying ...

The common-core math standards require that students learn the standard algorithm for multi-digit adding and subtracting—you know, the process in which you line the numbers up vertically to add or ...

Watch the video to learn about adding and subtracting with negative numbers on a number line and by using number discs. Adding and subtracting with negative numbers. Let's talk about two ways to help ...

You can find the difference between two numbers in more than one way. You can count up from the smaller number to the larger number. Or, you can count back from the larger number to the smaller number ...