Noted educator Carol Ann Tomlinson shares the insights that shaped her thinking about informative assessment. Informative assessment goes beyond tests and the grade book. It means assessing students both formally and informally in multiple ways and giving frequent, productive feedback on student work. Informative assessment isn't separate from curriculum or instruction; it spans student knowledge, understanding and skill. Informative assessment is about assessing students during the course of their learning to see how they're progressing. Although it looks at student readiness and student weaknesses, it broadens the scope to encompass student interests, students' preferred modes of learning, and student strengths. Tomlinson notes that the 10th understanding--that informative assessment isn't just for the teacher, that it involves a partnership between teacher and students--revolutionalized what happened in her classrooms.