Teaching special needs students

I am currently teaching classes in crochet and knitting at a local recreation center. I have 2 special needs students in the knitting class. One says she is in special olympics and she tries to cast on but seems to just make loops only to take them off the needle and start again (she doesn't seem frustrated just repetitive). I have tried casting on and knitting a couple rows so she has a base to work on, but after knitting (loosely) on that for a while she goes back to the simple cast on (adding loops on the needle, not the slingshot or knit-on cast on methods).
The other asked about knitting for the blind as she is losing her eyesight and wants to be able to knit when she can no longer see. I have heard that knitting is easier than crochet for the visually impaired to work on, but have not found anything to help her with that concept.
Both have just started learning to knit, and seem to do ok with easy garter stitch projects, but neither have completed anything as yet. The girl is making an effort to knit but doesn't seem to be making any progress. The older lady has a good start on a scarf then decided it wasn't wide enough so ripped it out and started over but made good progress in a coule of weeks between classes. She has "grand ideas" about knitting a scarf then a hat then mittens and then a matching dog sweater for her small dog. We have only one more class session before it is over until the next fall session.
Anyone have any suggestions on how to help either of these students?