Teaching should be done with passion. If the students are happy at the end of the day, so am I. If not happy, I must have missed something. I need to work harder to make them happy.
I have been a teaching in a institute of Computer Science (Programming and Database) for several decades and taught at the undergraduate and graduate level.
While teaching, I am more a mentor and organizer of learning experiences and situations, such that my students actively understand, reinvent and reconstruct everything they learn, than a simple transmitter of ready made and established truths imposed on them from outside. In other words, I avoid indoctrination and brainwashing. This means that I make use of the active methods, not the traditional or conservative ones, and appeal to due technology when it is appropriate.