Jonathan gained practice solving problems by subtracting to find sums - using the strategies of making a ten to subtract one-digit and two-digit numbers, using number bonds, and decomposing numbers. He refreshed his memory that writing numbers in a number bond is one way to show partners for 10, and adding counters of 2 different colors to a 10 frame is another way to show partners for 10. Jonathan was guided to recognize that breaking the teen number into a 10 and some ones helps him decide how to break apart the other number. Through practice using a variety of strategies, Jonathan has gained a more synthesized understanding of the relationship between addition and subtraction. Jonathan was encouraged to use number paths and number sentences to represent compositions when subtracting from a teen number; connecting the strategies helps Jonathan look for and make use of structure. For the last 15 minutes of class, Jonathan completed an assessment to evaluate his progress and understanding of prior material covered. He got 90% on the assessment, demonstrating his understanding that teen numbers can be decomposed and composed to subtract. Jonathan has been encouraged to check over his work. He required prompts to remind him to do so; the one error he made appeared to be due to his haste and not checking over his answers.