This article describes three reasons Twitter has become an essential part of US National Teacher of the Year Rebecca Mieliwocki's teaching life: (1) It provides professional development on demand by offering a steady stream of great new ideas, activities, lesson suggestions, book recommendations, and teaching tips that can be immediately applied to teaching; (2) It keeps teachers current and connects them to teacher leaders. Twitter allows users to follow key organizations such as NEA, ASCD, state education agencies, or the U.S. Department of Education to see the latest research, policies, or legislation. Teachers can also read about the top teaching talent's cutting-edge lessons or tried-and-true strategies and can ask them questions and get feedback on ideas; and (3) It provides teachers with a forum to reflect, get assistance and improve. The article concludes with helpful hints on how to get started.