CellCraft is a free interactive game were students learn about the cell as they play the game. It is free to download (as long as you give credit) in three different formats: SWF for embedding on webpages, EXE to play on a Windows computer, and APP to play on a MAC.
The creators are also developing a downloadable teacher's packet with more information about the game and lab for students to use as they play the game.
They also have a blog and forum on the site for users to share and get information and tips. There is a separate category in the forum for teachers too. http://cellcraftgame.com/forums/index.php?board=9.0
This is a fun way for students to learn about the cell.