Thank you for your message. When we do create editions of our books, it is mainly for grammatical revisions or game edits. As far as the main content, there is no major difference between the two. The games DVD is the same regardless of what edition you purchase. However we started adding the games DVD after the fourth edition was created, therefore the games DVD is only available in later prints of the fourth edition and all of the fifth edition printings. Please note that the games DVD can also be purchased individually (http://activitiesforlearning.com/mathcardgamesinstructionaldvd.aspx).
With your purchase of the Level C Starter Kit, unfortunately we cannot break up the package deal to incorporate another product. I do apologize that we unable to separate the packages.
I hope this helps, please let me know if you have any additional questions. We would be happy to help.
Make it a great day,
Activities for Learning-RightStart™ Mathematics
Our Mission: To help children understand, apply, and enjoy mathematics.