I've been fascinated by Mt St Helens recently.  I was in the third grade when it erupted in 1980 and remember it vividly as we were studying plate tectonics and volcanism at the time.  This time, though not as explosive, it's more interesting (I think) because there is some much up to the minute info on what's going on at the mountain available on the Internet.

If you haven't seen these links you should check them out: