Hi Kelvin,
You might want to listen to other frequencies as well: http://www.issfanclub.com/frequencies
Currently it seems ARISS has been shut down for an unknown reason.
Good luck!!

André

The most active frequency is 145.825 (packet) but it is been quite for the past 3 weeks (should change now that school events are starting up again). 145.80 is used for voice communications and occassionally for SSTV. Unless you are near the site of a school contact, you probably won't hear anything on 145.80 until the next interested crew member shows up.

Kenneth - N5VHO
http://spaceflight.nasa.gov/station/reference/radio/
Support ARISS http://www.amsat-na.com/store/donation.php (select "Human Spaceflight (ARISS))