I've previously written about the German educational system, focusing mostly on Gymnasium, Realschule, and the like. I wrote a bit more about the university system here.
Young Germany recently posted a really informative article about it here, if you want to read more.
These are just my thoughts on the educational system in Germany. I am not an expert, nor have I actually studied here myself. I've asked my friends for information. I know university students, researchers/PhD candidates, and a professor.