I got a comment yesterday from Jimmy D on this post with a link to LandNavigation.org and I thought I'd give it a look.
The site offers free downloadable lessons (20 in all) plus exams which cover the material. They're available in both PowerPoint and PDF format.
I randomly selected a lesson (Module 11 in PDF) and read through it. I think it's fantastically done and would encourage you to give it a look.
I can't imagine many land navigation "experts" who couldn't take something away from these lessons.
Thanks for the link Jimmy D.
Thanks for reading,