The book that I place in your hands, dear teachers, collects the experience I have had over 45 years in the exercise of the profession as a teacher at the primary, secondary and university levels. It brings the necessary skills that a 21st century teacher must master, taking into account the current of Constructivism and a competency-based approach, aspects to be put into practice in the classroom pedagogical process: At the beginning, development and closing. Likewise, it exposes the necessary elements for integrated planning, performance, motivation and communication in the classroom, aspects of strategies that favor student learning and a bit of competency assessment.