During the early years of presenting seminars and conducting workshops, I used overhead transparencies to display information. And for years and years, the transparencies worked okay.
And then I started to use an iPod connected to an LCD projector to display those same images and the whole thing went to a completely different level. Not only was I able to add color to what had previously been black-and-white images, I was able to project those new images large enough for an auditorium full of teachers to see clearly.
Due to the overwhelming response from seminar participants as to how I'm able to do what seems like magic, I thought it would make sense if I were to explain how easy it is to use an iPod as a presentation system in the classroom.
Although it's not completely done, there's enough there to get you started in the right direction.