Beginner lesson for adding two 2-digit numbers with regrouping (aka CARRYING) - meant for 2nd grade math. I first show the process alongside a visual model of base ten blocks, and then we practice it without it. Later in the lesson, I show a problem where the answer is more than 100, requiring three digits in the answer (but the addends are two-digit numbers). We also solve a word problem involving addition of three numbers. Check out also my other videos at www.mathmammoth.com/videos/