Where to Start

I am the Director of Technology for my school. Part of my job is teaching students as a "specialist" separate from homeroom instruction. I am doing my best to integrate into the homeroom curriculum and have really gotten the kids far with MS Office Suite. I was feeling really good about what I was teaching until I came here :) After two years on the job, I realize I need to do a better job of integrating web 2.0 tools into my lessons. I am on the awareness level of most tools mentioned here, but am overwhelmed as to where to start. I teach 1st-8th grade for two 40-minute periods a week.

Any suggestions for grade level appropriateness of each tool - wiki, podcast, skype, video production, flickr, website creation, blogs? Any great lessons/topics that you used to integrate with to provide me a source of inspiration?