Count back & use the relationship between addition and subtraction to subtract within 20. Warm up with a Mystery Math Mistake to find the error in DC's addition. Use ...

Help your child practice their subtraction skills and learn how to use a number line with this fun and easy activity. Fold up an origami football, decorate it like your favorite Cyberchase character, ...

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 ...