Fellow bloggers: Help!

Hi all! I decided to start writing a free blog. I make no money off of it, but love the concept of helping nursing students remember concepts of anatomy and physiology. My blog has just started a couple days ago. I kid you not, the big joke in nursing school, because I had the highest GPA, was, "There is something wrong with your brain. How do you remember all this stuff?" Well, now I am trying to offer a look inside the noggin'. I am starting off with a narrative of the cell being a bustling city. The reader can visualize a city that has people with specific roles and buildings with specific functions. This is how I remembered in school. I would also think of separate association that are completely random, but work (I.e. cytoskeleton: roadway in the city, but looks like a giant spider web that holds the structure of the cell, etc.) 

The problem that I am having is getting readers. Even though it is free, I do not monetize and I do not want to do sponsors, I do put a lot of effort into the blog and I want it to hit the right audience. How do I get my blog out there? People mention posting on my FB feed, but that is not hitting the audience that I am looking to gather. All my friends could care less, either not in nursing or not students. I have tried a couple of nursing FB groups, but they say "no self-promotion". If I am not really getting anything other than the self satisfaction of creating something really cool, how do I explain it is not self-promotion because that is what it looks like. Where else can I post, so I know that people can read it, provide feedback, and perhaps expand so then other people can also learn?