This Problem Set is a part of the Lesson 3, Unit 4, Grade 1. This lesson examines two-digit numbers as tens and ones, as well as just ones. Students use their fingers to represent bundled tens and unbundled ones by clasping and unclasping their fingers. For example, students model 34 with three students showing their hands clasped to make a ten and a fourth student showing 4 fingers to represent 4 ones.