This Fluency Activity is a part of the Lesson 13, Unit 1, Grade K. At this point in the module, consider introducing 6, either with 5 red and 1 white on the top row, or with 5 red on the top row, 1 red on the bottom row (like 5-groups). Focus on the transition from 5 to 6. Guide students to realize that it is, in fact, a crucial transition by discussing what they notice about the representations of 5 and 6 on the Rekenrek. Conduct the activity as outlined in Lesson 7.