Tom Whitby, one of the guys behind the weekly Twitter #edchat on Tuesdays has the theory that anybody who was a success in the surroundings of 20th century education (which certainly includes today’s teachers) is not inclined to question the process that they mastered as students. Telling a teacher that they should change their approach puts their whole career path in question.
They may be willing to take the chance to get yet another grade at the end of a course that was clearly outlined in a strong syllabus, but they are not frequently eager to splash around in a muddy, uncertain exploration of messy technology. It is even more a problem because the teacher wants to model mastery and success for the students in the classroom, not to model confusion to his/her students. Failure is the opposite end of the grading scale for a teacher whose life was mainly marked with As and Bs. To say a teacher is out of their comfort zone beyond the confines of a curriculum is generally an understatement.
For a while at my former school district, we had a set of locally run courses that allowed teachers to get credit for their explorations in classes run by their peers. It eventually died with administrative concern that too many people were getting credit that counted toward their salary increases for work that wasn’t part of an official college course. Too bad, really. A fairly large group of teachers came to classes that several staff members offered. Because the exploration was in a class structure, maybe the staff felt more comfortable. Maybe some of them did it only for the credits. Still, I would say that the students benefited from working with teachers who were comfortable with the tech in the classroom.