This professional development video clip shows students engaged in the first Common Core Practice Standard—Make sense of problems and persevere in solving them as learners make a decision about how much stain will be needed to cover the surface area of twenty-six completed boxes. Additional resources include a video transcript, teaching tips, and a link to a professional development reflection activity based upon the video. A related clip (cataloged separately) shows the same exploration by the same students but Common Core Practice Standard # #5-Use appropriate tools strategically is evident.