I started collecting vintage sewing books a year or so ago, from eBay. I have found many wonderful texts that teach beginning sewing from the early part of the 20th century. While you might not want to take it for an exact syllabus, I think that looking at some of them might get the wheels turning in your head.
"The Singer Sewing Book" by Mary Brooks Picken is a compendium of sewing information from the 1940's that is very appealing.
There is a series of small books from the Women's Institute of Domestic Arts and Sciences that is much more old fashioned but valid nontheless, with titles like "Cutting and Fitting", "Harmony in Dress", and "Dressmaking, Trimming, and Finishing". They were part of a correspondence course on the domestic arts, and form the backbone of learning for many sewing books that came afterwards.
I have a couple more that I could dig the titles out, but you get the idea. There is an emphasis on learning different types of sttches, understanding the properties of different types of textile, and lessons incorporating cutting and sewing of simple things.
While its obvious that you should teach sewing machine basics, don't forget to include hand stitches. I recommend that you have your students make little test strips of the machine stich types and different hand stitches and keep them in a binder for reference.
I hope that you will forge ahead with your idea - check out some of interesting podcasts out there too. Have you seen Threadbangers? While its more DIY and about refashioning, it is targeted to your deomographic. It might be fun to videotape some of your lessons and or results, for your own podcast or to send in to Threadbangers.
Just off the top of my head, I would teach Sewing Basics with a tote or pillow case or apron project involved. Kitchen towels, potholders, and teacosies could be a basic item as well. Then get into Sewing with a Pattern, and another one on DIY and Refashioning. You kow how frustrating sewing with a pattern and trying to get a good fit can be, so its good to have some successful results with other things.
Another avenue is to incorporate creative mixed-media sewing into one of your courses. Take a look at "Sew Somerset" in the sewing magazine section of Barnes and Noble or other bookstore. It has some really fun ideas to jump off in a new direction of the crossroads of sewing and art, by collaging cloth, trim, photo transfer, yarn, embroidery fiabers and a whole lot more....It certainly opened my eyes to a whole new way of looking at things. Many of these ideas can be translated into refashioning a la Belle Armoire.