Great review! Even though Mr lancer didn't always come off as the best teacher because of the way he treated Danny and favored the popular kids I think he was really great in this episode being a supportive teacher because he knows Danny can do better which he can if it wasn't for all the ghosts fighting that's one of the only things I like about his character other than the book references.
At this point I'm surprised Danny hasn't figured out Jazz knows his secret even though she's keeping it on the down low she is a really bad actress when it comes to covering for him he even ask her how she knows he has stuff to do after class and her only response is a sheepish smile.