I wanted to share the address for Promethean Planet with you. Promethean Planet offers lessons (flipcharts) across grade levels and subject areas. Although I'm not sure how well the flipcharts work with SmartBoards, at the very least this site may provide new or alternative ideas for lessons on the SmartBoard.
I have found some great flipcharts and resource packs to use in my classroom. My students really enjoy working on the Promethean Board. They often refer to or ask if we can revisit a flipchart that we have used in previous lessons!
You can find Promethean Planet at http://www.prometheanplanet.com/