National Public Radio's Money Blog has this podcast on the correlation between gross domestic product and kids, particularly schooling. It appears to be part of a longer series, so there may be more on GDP. I would think it can also be used when discussing coincidence, correlation and causation.
The podcast in this link is about 25 minutes long, so I'm not sure I would play it in class. However, some of you may be able to assign it or download it and put it on your class webpage as an ancillary resource for use next semester or next year when you discuss GDP and its importance.
If you have a chance, please share your reactions.