In classrooms where assessment for learning, commonly called formative assessment, is practised, students are encouraged to be more active in their learning and associated assessment. The ultimate purpose of assessment for learning is to create self-regulated learners who can leave school able and confident to continue learning throughout their lives. Teachers need to know at the outset of a unit of study where their students are in terms of their learning and then continually check on how they are progressing through strengthening the feedback they get from their learners. Students are guided on what they are expected to learn and what quality work looks like. The teacher will work with the student to understand and identify any gaps or misconceptions (initial/diagnostic assessment). As the unit progresses, the teacher and student work together to assess the student's knowledge, what she or he needs to learn to improve and extend this knowledge, and how the student can best get to that point (formative assessment). Assessment for learning occurs at all stages of the learning process. Researchers whose work has informed much of this assessment reform include Ken O'Connor, Grant Wiggins, Jay McTighe, Richard Stiggins, Paul Black, Dylan Wiliam, Chris Harrison, Bethan Marshall, Gordon Stobart, Caroline Gipps, Joanna Goodman, Thomas Guskey, Damian Cooper, Philippe Perrenoud, Royce Sadler, Bronwen Cowie, Margaret Heritage and Ronán Howe.