Writing a course

So, I'm getting ready to start on a new project, where I create courses, teaching people how to write code. I know a number of languages, so it makes sense for me to do it. The course falls into "occupational therapy" category, and it's a good cause.

But here's my dilemma:

If the goal is to get these people marketable, quickly... do I teach something that's easy to learn?
Or something that's in high demand?

I could teach a course on Javascript as easily as I could teach a course on Go or .Net.
I have full creative freedom and autonomy here. I can teach anything I want.

What do you think?
What would you do?