FOI Changes
So I spent an entire University quarter studying the ASA question bank book as well as the Jeppesen CFI manual as they were the only required material for my 141 ground school.
Then... 4 days before my FOI, my instructor emailed me the link to the Aviation Instructor Handbook. Apparently that's the only source for the new FOI questions.
You need to download the PDF from the FAA and study that book.
I've never scored below a 95% on any FAA written exam, and while I still managed a 94 on this one... I felt completely duped by the process. The FIA was even worse.
Don't know much about the King materials, but I can guarantee that the Aviation Instructor Handbook is all you need.