Officially, Bildung means education. The German Department for Education is called the Bildungsministerium. Volksbildung is what the Nazi government called social education (they had a department for that, too).
In literary terms, as discussed above, a Bildungsroman is a novel about the "growth" or "development" of a character.
Novels such as "Jane Eyre", "Great Expectations", "Der Gruene Heinrich", "Wilhelm Meisters Lehrjahre" all share the qualities of a Bildungsroman, in that they show how and why the protagonist changes and develops morally and psychologically throughout their life.
Interestingly, the word Bild in German means "picture". So Bildung means the creation or formation of a picture (if you were to think etymologically). Therefore, a Bildungsroman paints a literary picture of the hows and whys of a character's development from foolish to wise, naive to experienced, innocent to tarnished, and many other possibilities.
A great questions!
I believe that the right translation in terms of bildungsroman is "education". Much as the other definitions such as "shaping" could apply best to material objects, education is what applies to the character of a person. Once you get education, you have been "shaped" but the true action is the education, shaping is a way to describe what has happened to your character/soul/mind through your education.
This in an interesting question, especially since I have German ancestry. :) I had never thought to examine it beyond the word "bildungsroman" as a coming of age novel. I did a little quick research and came up with this:
Bildung, on the other hand, can be translated into English as 'education;' it equally can be taken to mean 'formation,' 'growth,' 'shaping,' 'cultivation,' 'civilization,' or 'refinement.' Bildung is not limited by specific goal-orientation, nor is it passive. Bildung is ongoing, unlimited in scope and most importantly, encompasses the whole person. No one leads you anywhere. Material is made available, but it is up to the student to put it to use. Bildung is the education you give yourself.
I look forward to what others have to add. Thanks for the opportunity to open our eyes!