Looking for scales over chord progressions lessons.

Well, a lot of times, you can use one of many scales(i.e. Pentatonic, major, minor, etc...). This usually takes experimenting, and many times, more than one scale will work. Naturally, you use the scale in the same key as the chord that you're playing it too.

Yes, I'm aware of all that. But to find something that can be used with students would be a tremendous help.

It's a big grey area for most people learning scales as to how know how to apply them, and I'd hope to find something in print to speed the process up. Just because somebody learns a half a dozen scales, doesn't mean they know which one to use when jamming. They need to learn how to decide, based on the information they have... they need guidelines.

It's much like deciding what fills to play when playing in a free form environment, versus doing a cover version of a song where it's already scripted.

Obviously the ear is the end judge, but one has to have some knowledge beyond knowing the Key and some scales.

Seasoned players seem to always know where to go and what to play when improvising... so how does one get to that point faster? What training methods should be studied?

If your interested in a book, this might be what you are looking for: "Scales Over Chords." It comes with an audio CD. It goes over scales and chords in all the modes using the CAGED format, so there is a lot of unnecessary repetition. But there is a lot of information spelled out pretty clearly, so it might be what you are looking for. I got it at Barnes and Noble, but I'm sure Amazon would carry it.

I believe students should know the "naturally occurring" chords in each key , so that they only need to think in terms of one scale until a "non-key" chord comes up. It makes things a lot less complicated.

The Complete Johnny Smith Approach to Guitar

It's a gold mine of knowledge of scales in relationship to chords.