Master’s in computer science or free online classes? I am currently deciding my next step in life and am pretty confused about my options. I am an English language teacher with an MSEd in TESOL and have a growing interest in both computer science and linguistics. I have been considering getting my PhD in linguistics, possibly with a focus on computational linguistics, but I also am really interested in beginning to develop applications, especially ones related to language and education (i.e. Android apps, python-based language tools, etc.). 
I have little math experience, but do have some client-side programming skills (HTML, JavaScript, PHP).

So lately, I have been considering getting an MSCS (online) in order to build the requisite skills and also enhance my job prospects (a language teacher doesn't make much).
I've been looking at online programs that offer courses in AI, MT, NLP, and human-machine interaction. But, I've also been considering skipping the MSCS and doing Coursera, CodeAcademy, and other free tutorials to learn the development skills, then making some GitHub or publishable projects. I have done CodeAcademy for Python and picked it up pretty quickly. The problem with these free education sources, however, is that I lose motivation quickly. However, If I had paid for them, my motivation would be sustained because I spent the money and want to get my money's worth.

So, my vague question is: Do I do a MSCS or focus on what’s freely available, build my skills, and hope I get good enough to not need a real credential?


  Moderator’s notice: Please do not take this as a shopping question and suggest specific courses.
What OBu said: This is going to depend on what your goal is. 


If you want to work as a programmer, generically, then a MOOC might be a good way to skill yourself up. As far as studying, fundamentals are going to pay off no matter where you work: Algorithms, Software Engineering, Math, etc. The problem with MOOCs is that it's not clear if they are going to get you through the door when job hunting; so be sure to focus on creating work that can demonstrate your skill, and help get you over that barrier. 
If you want to create research, write papers etc, then you could always try to create your own research program. Having said that, if you don't have an established history of auto-didacticism then this is going to be difficult to maintain. A real masters program helps guide you down paths, and force you to prune those search trees.
If you want to work as a programmer, in the NLP/MT/AI fields, then you might have to do both: MOOCS and an MSc. 


A side note; be warned that there are lots of MSc. programs out there, varying in style and quality. Some are essentially just more courses, while others are intended to produce new research. Be sure that the MSc. program you register for is going to get you what you want. Do your research.