Trade it with base-ten blocks
Build both numbers with blocks, push them together, and make every trade out loud: "Twelve ones? Trade ten for a rod!" Do it once with blocks, then once with quick sketches, then on paper. Kids who can show the trade rarely forget to carry.
Why it works: kids understand an idea best when they touch it, then draw it, then write it, the order the U.S. Department of Education recommends for elementary math.
Try it withTriple Digit Addition Regrouping WorksheetWorksheetsOpen it →























