Gabe taught our class as a sort of permanent sub, as the teacher originally intended to teach our class was out for the semester.
Gabe had this weird video game system for the class, consisting of 'Modules' 1-10 and 'Bosses' A-C. You could retake any of these assessments as many times as you needed until you passed, however you had to get it 100% right to pass. Each module was 1000 points, and each boss was 2000 points. A "B" was 8000 points, going up or down 1000 points for each 1/3 letter grade (B+ 9000, A- 10000, etc). He encouraged everyone to work together because each person was individually collecting points so there was no curve.
Anyone who wanted to do well in this class had the opportunity to. I am terrible at physics, but I still achieved an A- in this class. Gabe offers copious amounts of 'quizzing slots' virtually any day of the week, and you could keep hitting your head against the wall until you passed it. On top of that, Gabe hosted lots of office hours (I really mean a lot, I don't know if he sleeps) in addition to the recitation and TA office hours. He would also stay multiple hours over his time slots to help students with specific problems. The class had 200+ students, and he knew the name of everyone who showed up. Even now that I am in the second semester of physics and he is not teaching a section, Gabe still holds review sessions for his former students to help them understand concepts.
Very dedicated to helping his students
Weird quizzing system, no exams