Assessment That Informs Teaching and Learning by Cris Tovani. This author articulates clearly and succinctly why assessment is so important and how to make sure that it is meaningful.
Some of the highlights include her comparison of teaching to coaching. Also her explanation of how assessment should be differentiated to meet kids needs and goals is clear and understandable.. She also does a great job differentiating between the meaning of hard and rigorous.
She integrates specific methods she uses, as well explaining tenets that might allow a teacher to produce her own tools and methods of assessment. The emphasis is on formative assessment and making that assessment useful to the student.
I am considering using this book for a teacher study group that I plan to facilitate at my school. It is a quick easy read, but I already know that I will be thinking about some of the points she makes for a long time to come.