I''ve been taking the USAPS courses for a number of years now - I''ve earned a JN for celestial navigation. In my years of taking the courses, I have not found an emphasis on wooden boats or western rivers or anything else along those lines. While national does write the tests and textbooks (which were updated within the last 2 years) much of the flavor of the courses rest with the individual squadron.
I found that my instructors gave a nod toward GPS (and Loran) where appropriate, but always with a caution and also with the advice that you can learn it easily from the instruction manual; they were not going waste classroom time on something you could do just as easily yourself.
The first squadrom I joined consisted mostly of power-boaters, so I looked around and found another local squadron that was 80% sailors, and it did make a difference. Depending on where you live, you may not have a choice, but check around.