I have developed my own song based system for teaching acoustic guitar, which is quick and easy to learn, and gets you results very quickly (as long as you practice).
My system is different because it can always have vocals in mind, because most people who play guitar want to sing too (they just don’t think they can do it).
There is also a heavy emphasis on rhythm because that’s where so many beginners go wrong, and developing a natural sense of rhythm is essential (especially if you want to sing too...)
Many of my guitarists move over to singing at some point, after all, guitar and vocals are a match made in heaven right ? But it is entirely optional.

Check out my Bare Bones - Acoustic Kickstarter course for beginners  <span style="color:#c0392b;">HERE</span>