One of my favorite courses to teach is International Baccalaureate Mathematics.  This course includes Functions, Number and Algebra, Geometry and Trigonometry, Probability and Statistics, and Calculus.  It is a two-year course and I get to learn, relearn, discover, and explore mathematics as a practitioner as well as a student.  I love watching the “aha” moments of my students as they progress through the course.  Often, I learn new ways to approach problems from my students and I fall in love with the Math all over again!