Okay, so your scholars are excelling at two-addend addition problems, but what about three or four? Here are some practice problems to stretch their math skills. They find the sums of six equations: two with two addends, two with three addends, and two with four addends. This will require regrouping, and all numbers are double-digit. Because there is an explanation below these problems, consider projecting this as an all-class warm up. Collect learner responses before revealing the step-by-step answers.