What are the thoughts of the educational community on the practice of building extra credit questions into a quiz/test? I have done it in the past, in the hopes of allowing students who would otherwise "bomb" the test to bump up their grade a bit. My experience has been, however, that it actually further polarizes the result. Those students who would have gotten A's anyhow now get monstrously high scores...and the poor performers, lacking a solid knowledge-base for the regular credit questions as they do, lack the knowledge base to get the extra credit as well. Any thoughts or other ways to go about this?