This Fluency Activity is a part of the Lesson 1, Unit 1, Grade 2. Decomposition of single-digit numbers and 10 is a foundational skill for fluency with sums and differences to 20. For students who have not yet mastered their pairs to ten, use fingers as models. Have students show the larger addend on their fingers and encourage them to look at their tucked fingers to determine the partner to make ten. Assign Partner A and Partner B. Students write the target number, 10, in the circle at the top right of the target practice template.