Addition & subtraction strategies to solve two-digit equations using an open number line. In this lesson, students go over using different addition and subtraction strategies to solve two-digit ...

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 ...

Explains the concept of zero in mathematics, emphasizing its role as a number that represents the empty set. It illustrates how zero is used in addition and subtraction, showing that adding or ...

This is a preview. Log in through your library . Abstract A learning/teaching approach used base-ten blocks to embody the English named-value system of number words and digit cards to embody the ...

What is a number line? A number line is a straight line with numbers written in order from lowest to highest. Number lines can go up to any number, such as 10, 20, or even more! They help you to see ...