I know there are several academics in the blogosphere, and I direct this question to you.
Suppose you have a lecture class with 500 students. You meet 3 times a week for 50 minutes a session. In this case, the class is an introductory science course, which is semi-relevant. Probably 90% of your students have never had any of this material before: all new terminology, images they don't recognize etc. They also have a separate weekly lab where they can start applying their new knowledge, actually touching and seeing these bits with their own eyes.
How would you set up your lecture?
Would you use powerpoint or the chalkboard/whiteboard, or a combination? How do you engage as many students as possible in a 500 person class? Is it possible to have anything resembling a 'discussion' or any real feedback in that setting?
Thankfully I'm not the one in front of the room. I am a lab TA however, and the lecturers are interested in the input of the TAs to try and improve the class. I personally favor using powerpoint, with the caveat that you must avoid 'wall of text' syndrome. Intersperse the factual slides with images illustrating your point.
Opinions or ideas? There is a very real chance that somewhere down the line I *will* be the one in front of a class this big. May as well start planning for it now.