Learning 2.0 - RSS

Creating a RSS seems to be quite simple - managing it seems a little harder. I can't quite seem to work out how to get rid of the feeds once I've read them. I tried the "help", but still can't do it.
I subscribed to the Powerhouse Museum's picture of the day, as well as some preset feeds from Bloglines including the Librarians' Internet Index and a comic of the day and joke of the day. I found a site which has free craft projects for kids, which I'll use as I'm co-ordinator of Storytime. I also subscribed to a few book & movie review feeds. I must admit, having 10 feeds for each site pop-up within seconds of validating my membership was a little daunting - though I did find something straight away that I could use.
Once I figure out how to manage the feeds, I'll be a lot happier.