If your students are confused about carrying and borrowing, this unique way to teach these concepts is just what you need. This dragon themed unit explains how to use pinto beans and Zip Lock bags to show your students, in concrete terms, just what is happening when they carry and borrow. And what about that dreaded process of borrowing across zeroes? This method will make it a snap. The unit covers common core standards in 2nd, 3rd, 4th grade math.