carla,
For me, it's all about learning. If course objective are not met, then giving extra credit is only about grades, which may have little to do with learning. I teach a medical program where essential material must be mastered. My view is there can be no subtitute for learning the essentails. I'm sure no one would want a medical professional working on their loved one who was an "A" student, but was unsafe or negligent in thier duties.
Barry Westling