First a bit of a background to my answer. In the days before digital cameras were widely available (or available at all), people asking "what camera should I get to learn photography", answers would tend to go along the lines "get your self an old, manual camera so that you learn from the ground up". I always found that rather stupid. If you stick a manual camera in the hands of a newbie, chances are that all images come out completely crappy, exposure way off and so on. I can't see a more efficient way of killing and aspiring interest in photography. My advice was always the opposite; get something fully automatic (but with manual capabilities), and focus on the image. The rest will come.
Different people will have to approach the subject in different ways. Photography has two sides; the technology and the image. I have seen plenty of stunning images captured by people of haven't got the slightest clue about aperture, or ISO settings or shutter speeds. All it took was an eye for a good image. I have seen fewer great images from technological virtuosos without an artistic eye. Of course, it helps if you can predict the result in some way by knowing the technology, but I would argue that it is not strictly necessary to know all about how aperture, shutter speed and ISO are chained together.
So, I would say, start off with the image. Dive into composition, what makes an image more or less interesting. These discussions will most likely spawn threads into the technological field (How do I get the background more out of focus in my portraits?" or "How do I get more of this landscape to be in focus?" - start talking about aperture and how it affects depth of field - "Wow, how can I do to capture the feeling of speed when that motorcycle drives by?" - start talking about shutter speeds). When there are specific cases to talk about, it is often easier to learn. When a beginner has captured an image that they feel proud of, but perhaps wonder how it could get even better, there is a hunger for learning that will make things so much easier.