Interactive Addition and Subtraction on the Number Line (3rd Grade)

Dream Box - Addition on the Number Line Using Landmark Numbers.  Using an open number line, students leverage landmark numbers such as tens and hundreds to solve addition problems.  Lesson

Dream Box - Subtraction on the Number Line Using Constant Difference.  Using an open number line, students explore a compensation strategy as a vehicle to create friendly numbers to solve subtraction problems.  Lesson

CCSS.MATH.CONTENT.3.NBT.A.2
Fluently add and subtract within 1000 using strategies and algorithms based on place value, properties of operations, and/or the relationship between addition and subtraction.