Tonal A Schenkerian Perspective features bite-sized chapters that help students recognize Schenkerian concepts in music and show them in analyses. An innovative new analysis pedagogy guides students through the process of producing their own Schenkerian graphs.
This could potentially be great as a supplement to a different introductory text book, but it isn't marketed that way. Damschroder's "bite-size" chapters are enough to get through one-a-week and finish within a semester, but the brevity comes at the cost of necessary rudiments. You begin off graphing, which is awesome, but there is never a really solid explication of the graphing mechanics - instead, Damschroder dedicates that precious space to introducing his own unorthodox concepts and kinda weird prose. Those in themselves aren't bad, but I've diligently worked through the book and all of my graphs still feel like (under)educated guesses.
Maybe not a bad textbook on Schenkerian analysis, but certainly a mediocre introduction. I expect a second edition could easily fix a lot of what is missing here, but I guess I'll give Cadwallader & Gagné a shot in the meantime.