Yasuko Yamaguchi helps students add two numbers using an open number line. Yasuko Yamaguchi helps students add two numbers using an open number line. Let's Learn is available to stream on pbs.org and ...

Which order should you add two numbers? Numberblocks Two and Three have the answer: you can add two bananas to three bananas, or three bananas to two bananas and the total stays the same. It's five ...