This Fluency Activity is a part of the Lesson 9, Unit 4, Grade 1. This activity reviews yesterday's lesson. Write sets of four numbers within 40 (e.g., 23, 13, 32, 22). Students write and read the numbers from least to greatest and then from greatest to least. Ask questions such as the following: How could you use the words greater than or less than to compare 32 and 23? Which number has the same digit in the tens place and ones place?