Some teachers are considered "cool" by their students, but their approach to instructing their pupils should not be governed by a desire to be popular with pimply-faced adolescents.
Teachers must guard zealously and impart enthusiastically the subject matter with which they have been entrusted and to which they have devoted their life's work.
They should never distort or depart from their subject matter just to facilitate some "fun" activity or to flog some personal viewpoint.
This "geography teacher" seemed to be doing both. He was souping up geography to stroke his own ego.
When I teach, I constantly remind myself, "It's not about me!"
I think there are also cool teachers in the sense that he presents everything clearly and thoroughly and in an easy-to-understand manner. It must be noticed, though, that most adolescents may not "appreciate" such teachers!
I remember a few teachers in high school that I consider cool: one teacher always called back to basic foundational principles in 5th Form (equiv to US high school Sophomore) chemistry such as moles, empirical formulas, etc when we got stuck. He also extended the teaching materials and included something about acid-base concepts that were not examinable until 7th Form (senior) but which helped us immensely in understanding 5th Form materials (of course he didn't set any tests on these extension materials). Another teacher in maths taught all the common tricks in problems such as solving (2x - 1 = 2x + 3).
Of course, bad teachers are those that actually refuse to really teach anything, those who actually thought he had gone over a topic but in reality hadn't (I had one teacher like that when in high school - and it produced confusion in the class). I'm sure that most of the students in Mr Bennish's class would consider opinions like mine as from nerds.