This is a SMART Notebook lesson aligned with the Everyday Math program for 1st grade, lesson 2.4. It introduces the concept of unit labels and unit boxes, which are used henceforth throughout the Everyday Math program. Included are mental math pages featuring interactive number grids for counting practice and a brief lesson on unit labels. Also included are pages suitable for modeling the use of a calculator, which is used for the first time in the program during this lesson.