Throw out gradebooks and meet the assessment system of the future!
Mark Barnes's formula for feedback, titled SE2R (Summarize, Explain, Redirect, Resubmit), has delivered stunning results to the forward-thinking schools that have tried it. The method in this book will loosen and then break your classroom's dependence on the "A-through-F" grading system that does little more than silence student voices.
Delving into what really motivates students, the book covers:

How GPA is a classic example of "the tail wagging the dog"
Utilizing mobile devices and social networks to maximize the benefits of SE2R
Addressing and overcoming bureaucratic resistance to change