Casey with DreamBox Math Classroom just contacted to let me know about an offer for Pre-K-2nd grade teachers going on right now:

For teachers/schools:
DreamBox Learning K-2 Math is now offering Pre-K to 2nd grade teachers free classroom subscriptions for in-class use of DreamBox K-2 Math from now until the end of the school year (June 30, 2009). Teachers can go to www.dreambox.com/teachers to sign up for a teacher account on DreamBox, preview our lessons and our curriculum, and apply for a free classroom subscription for in-class use through the end of the school year.
DreamBox Learning is an effective, award-winning online math learning product that dynamically adapts to each student. Based on national standards, DreamBox provides more than 350 math lessons covering number sense, computation and problem solving in an engaging game experience that kids love! And teachers have the ability to track individual student academic progress through the in-depth math curriculum.