One of my guitar students has both learning issues (minor) and dyslexia (major). My school of thought was to make lessons more infrequent and fun than some of my other students in the hopes that this would keep him playing. That has worked to some degree, but the problem is that he isn't progressing much at all and even less in the area of reading music (getting students to be well versed at reading sheet music is one of my biggest strengths and calling cards as a guitar teacher). Maybe I just need to focus on chord progressions but I think that will be a challenge for him to retain even that knowledge. What have you found works well for your students with these challenges?
I am not a certified instructor with training for learning disabled students but...
I play guitar and have dyslexia (which has a differential diagnosis of auditory processing disorder).
I think less frequent lessons would back fire. If the student seems capable of accomplishing something frequent interaction would be supportive. I can say from personal experience that people with dyslexia, especially untreated dyslexia, can have problems understanding why they need to work so hard to do what others seem to be able to do easily. If you are interested in helping this guitar student you may want to search for some basic info on what to expect from a dyslexic student. You should also be prepared to deviate your standard approach to suit the student's learning style. As long as they are having fun and excited to keep going then it's working.
If they seem better at ear training than sight reading, or if they seem to like the geometry of chords, then you can use that as a hook to teach another musical concept.
It took me a long time to get good at sight reading but it eventually took. Not progressing can be disappointing to both of you. One thing for sure is negative feedback will be amplified in the mind of many learning disabled students. Whatever progress they are making is "normal" for them. But I would avoid long periods between lessons. Rather than really working on the one thing they were taught they may likely feel isolated. Again, lots of feedback on the same topic reinforces it.
Not knowingly having taught guitar to a dyslexic, the experience may not be in my inventory. However, there are many different approaches to teaching an instrument, and it's totally not necessary to use the medium of written music. Dyslexics find deciphering squiggles written down very taxing and confusing. Music doesn't have to be that way - except you have as your forte the propensity to use that as the main medium.
It doesn't seem to be working - hence the question. So, a completely different tack needs to be taken. maybe with no reference to anything on paper. Chords tend to come in families - C F G; A D E; F Bb C, etc. Many songs use three and there's no need to do anything except get the student used to playing round with 'three chord tricks' to start with. There's always the ubiquitous pents to make up tunes from for a change.
Most of us have weaknesses, and compensate for them in other ways. I'm sure dyslexics are no different - finding reading difficult? Then I'll use memory or repetition or some other strategy so I can get the job done! You, as teacher, need to find what it is in that particular student, and work to his strengths. Yours may be dots, but that has to go out of the window here! And I don't understand why more infrequent lessons could be advantageous. I'd tend to keep them the same as anyone else's, only to change - either way - shorter, more often, or the opposite - when I'd established what may be more productive.
Dyslexia in itself has not been a reason not to achieve in life. Lots of successfuls have it. And they're successful despite it, having found ways round.