Blogging/ Breakthrough

I am wondering how you set up the whole blogging interface. I understand the posting part but am a little confused on the set up process. Also how to students post in your classroom. Do you have laptops for each student in your classroom? How do you get music?
Now I realized that I probably should have commented on something that we read. While reading Breakthrough I was happy to stumble across Nanci Atwell support on prewriting processes.
Keri says I am a grandma. What can grandma can add an MP3 file on her post. Not Keri!