About This Lesson
This is a sample task from achievethecore.org. The purpose of this task is for students to solve word problems that call for addition of three whole numbers (1.OA.2), to relate counting on to addition (1.OA.5), and to understand that the two digits of a two-digit number represent amounts of tens and ones (1.NBT.2). This task supports developing conceptions of counting on and base-ten structure, and is thus appropriate early in the school year
