Programming exercise Tagging I wondered what attempts were made to use tag(s) with programming exercises so that anyone can search / find (etc.) exercises just like books in a library.

For example (in user story format):


As a student in Java, I would like to find exercise on recursion.
As a student, I would like to find MCQ exercises for iteration
There are a lot of reasons this hasn't happened, and probably won't. The first is that the exercise would need to be published somewhere that was effectively searchable. Some instructors will post exercises online, but not all. Many, in fact, want to keep them private so that they can reuse them in the future. Posting them online often leads to bad behavior, such as searching for solutions, rather than actually doing the exercise as intended. 

Another problem would be the establishment of a consistent set of tags. For a small site such as this one, it can be done, even if imperfectly. For the entire world wide web it would be a much harder (impossible?) task. 

But if you have done all of the exercises in your course textbook and yearn for more, you can often find books of exercises on various topics. I think this used to be more common than now, but for some subjects they can be found. I remember Schaum's outline series in the past. The still seem to be in print. 

Your course instructor can, perhaps, loan you another textbook with even more exercises.