Hi Eliza,
I believe the best courses have FLEXIBILITY. As a former Kaplan and Grockit teacher, and as someone who has worked for MANY smaller test prep companies, I found the biggest frustration as a teacher to be having to deliver the SAME material in the SAME way for EVERY student, regardless of their natural abilities and learning-style. It's incredibly frustrating for students, because they are essentially given the same material to learn by rote as every other student, and it's incredibly frustrating for teachers because we cannot pick and choose material to address a specific students weaknesses.
I think it's worth exploring which courses are actually "adaptable" to the skill-level and abilities of their students. My guess is very few! It's a real bummer, and one of the reasons many former teachers such as myself become private tutors.
