The National Board certification process prizes the concept of “teacher as learner.” Core Proposition 2 states, ”Teachers know the subjects they teach and how to teach those subjects to students.” During the National Board certification process, the comprehensive subject matter test can be intimidating, especially for teachers who are accustomed to teaching a specific course within their subject area. Kyna Schutzbach, a math teacher, confirmed this: “At the time I had only taught geometry and was just beginning to teach calculus. The required tests covered a variety of topics, so I had to go back and study some math that I hadn't done in a while. I do think it's useful for math teachers to be confident with topics covered at different levels. It's easy to get stuck in one subject which can make it difficult to relate the material to other areas.”Knowing the range of one’s subject matter is only eclipsed by knowing one’s subject area in depth. Schutzbach shared, “I have been a reader for the AP Calculus AB exam for the last five years. This experience is definitely the best professional development that I have done. Every year that I have participated, the calculus reading has been in Kansas City. We work for seven consecutive days grading AP Calculus exams taken by students around the world. There is no better way to learn the subject than to explore all the ways that students approach each problem.”In order to stay abreast of current trends in one’s subject area, National Board teachers embrace Core Proposition 5: “Teachers are members of learning communities.” Schutzbach’s experiences as a reader for the AP Calculus exam provided her the opportunity to network with other high school teachers and college professors. “The relationships built with these colleagues are valuable all year long. We share ideas of how we teach and what methods are most successful.” One best practice that Schutzbach incorporates into her classroom is frequent feedback. “Quizzes and tests are always returned the next day, and students are allowed to keep all of their work. This allows me to carefully monitor their learning and provides them the feedback to correct their mistakes before they become bad habits.”Though National Board teachers are subject-matter experts, they are also model lifelong learners.