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.