i was unbanned today 
hmm, i don't know any podcasts, but maybe there's some on iTunes...? Well, there's some video lectures from 東京大学, but i guess that's above what you need... but, half of NHK's programs are audio only anyway actually, so you could try downloading those...? http://forum.koohii.com/viewtopic.php?p … 85#p113485 (i haven't yet tried this though, so don't know if it works on the audio)
If not, you can still learn vocab from the PDFs and listen for it again when you watch.
Here's another video series aimed at high schoolers who want to get into good universities: http://kyoyo.wao.ne.jp/kouza/?theme=&pageNo=1
and here's the NHK schools site in general: http://www.nhk.or.jp/school/ . There's more shows on there, http://www.nhk.or.jp/school/bangumi.html but they're aimed at a lower level. But if you're finding the high school lectures too much, you could build vocabulary with these.
It sounds like you haven't got much time left, so maybe save this to do in your Japanese time... anything you learn can be a bonus then. And it can help you keep focused on schoolwork even in your Japanese time... 
Don't forget the Khan Academy! It's in english, but he does explain things well! http://www.khanacademy.org/
Last edited by IceCream (2011 February 15, 6:59 pm)