SJS Teacher

I have known about podcasting for quite some time now and I know a couple of teachers from school who use it quite extensively. I think I can make use of podcasting quite well in my professional/personal development. I have already added a couple of interesting RSS-ready podcasts to my reader such as the NASA and Scientific American poscasts. I am not sure though how I can use it in the science classroom. Of course my students themselves could subscribe to podcasts but I need to see them actively make podcasts and not just passive receivers of them. I need to research for more possibilities for this.