In this increasingly flattened world, learning to think critically about global affairs is of utmost importance. Students need to learn how local and global affairs are interdependent; they need to be able to identify shared interests and to collaborate with others across national borders. Twelve Lessons to Open Classrooms and Minds to the World is the result of a collaborative effort organized by the NEA Foundation to support outstanding teacher-leaders in developing 21st century global curriculum that is aligned with the United Nations (UN) Sustainable Development Goals