Unit 1 Addition Within 20 In this unit, children work with place value, representing numbers in different ways, and comparing numbers. They add two, three, or four 1-digit numbers, sometimes resulting in new tens. They will also work with a variety of different word problems with missing addends, missing information, two step problems, etc.
Visual models and real world situations are used throughout the unit to help children understand the value of 2-digit and 3-digit numbers and how to find the sum of 2-digit numbers.