Adding Within 1,000 Using an Open Number Line

This lesson teaches how to add numbers within 1,000 using an open number line. It reviews place value and the commutative property of addition, demonstrating how open number lines can visualize addition by hopping in increments of hundreds, tens, and ones. The lesson also covers alternative hopping strategies and solving equations with unknown addends. By the end, students will understand how to use open number lines flexibly to find sums.

How do you determine the order of hops when adding numbers?

Explain how to fill in the blank in the equation 351 plus blank equals 738.

What is the final answer when adding 351 and 387?