Formative assessment – the secret to lasting improvement in schools

School improvement can be complex and nuanced, but the core idea is relatively simple: improving student outcomes starts with improving the quality of teaching and learning. One of the most powerful tools to achieve this is formative assessment. This blog explores why formative assessment, with its focus on continuous feedback and adaptation, is crucial to enhancing both teaching quality and student success.

Formative assessment is often misunderstood as a simple check for understanding or as a tool for demonstrating progress within a single lesson. However, it is much more than that. It is an ongoing process that involves using feedback to adapt teaching to meet students' needs. Importantly, formative assessment should not be seen as a one-off technique but as an integral part of the learning process that engages both teachers and students.

Another challenge in defining formative assessments is variation in how teachers have been trained. Personal experiences with formative assessment can vary significantly, muddying the waters. This became evident during one of our networking meetings for Kent maths leaders, where a lively discussion emerged about whether end-of-year assessments are formative or summative. A shared understanding of terminology is essential in such contexts.

It is surprisingly difficult to define formative assessment since it has been associated and wedded to many teaching and learning phrases: assessment for learning, assessment of learning, adaptive teaching, responsive teaching, mastery teaching and others. All these descriptions highlight merits and aspects of the broader definition of formative assessment, and they are often used interchangeably, despite their differences.

For our definition, there is no better place to go than ‘Inside the Black Box’ by Dylan Wiliam and Paul Black (1998):

There is lots to pick out and go through here (note the student’s involvement) and I will save that for later posts. Often cited as ‘responsive teaching’, this does still fall short of the broad definition that Black and Wiliam are attempting to convey by also considering the role of the learner.

Wiliam and Leahy (2015) translated this definition into a set of evidence-based strategies to support learning. These five strategies capture the complexities of teaching and highlight the critical roles of both teachers and students. They go beyond the misconception that formative assessment is just a gimmick or a technique for demonstrating performance—or worse, for showing progress within a single lesson. The strategies summarised below represent both the direction and the stakeholders involved. In the following posts, I plan to explore each of these in detail.

It is worth separating the differing levels of assessment that occur within schools into long cycle (across terms and units of work), medium cycle (within and between units of work) and short cycle (within and between lessons - minute by minute). All of which can be argued to be formative at differing levels and purposes. This broad range of assessment can be ripe for misunderstanding and by what we mean by formative. Such as, ‘are end-of-year assessments formative or summative?’

While formative assessment can take place over long, medium, or short cycles, research consistently shows that short-cycle assessments—those that occur within and between lessons—have the greatest impact on student learning. Over 40 years of research, including studies by Natriello (1987) and Black & Wiliam (1998), demonstrate that short-cycle formative assessments yield the most significant gains in student achievement.

We know teachers make a difference and we know that students taught by the most effective teachers will learn in six months what those taught by an average teacher will learn in a year (Hanushek & Rivkin, 2006). We also know that in classrooms of the most effective teachers, students from disadvantaged backgrounds learn at the same rate as those from advantaged backgrounds (Hamre & Pianta, 2005).

Designing professional development programmes in schools and formative assessment go hand in hand. In fact, considering the leading of teacher development within schools could also be framed within the five strategies. Simply replace ‘students’ with ‘teachers’ within the strategies and the same principles apply for leaders and is helpfully summarised in Nick Hart’s blog post: Formative assessment and school improvement as:

• clarity of goal / direction around the problem that we are seeking to solve
• build knowledge of the extent to which colleagues understand that direction and are moving towards it
• make adjustments to the support we provide to colleagues to clarify their understanding and remove barriers to better understanding.

What if developing formative assessment strategies can support and reduce some of the many stresses of opportunity cost? Who doesn’t want students to be owners of their own learning (strategy 5). Is this not the holy grail of teaching and learning and a massive workload win. For now, I will leave the quest for the holy grail, and I will explore this is much more detail in another post.

While implementing formative assessment can drive significant professional growth, it’s not without its challenges. Many teachers find it difficult to balance the demands of daily teaching with the need for continuous development. However, by embedding formative assessment into everyday practice, teachers can reduce the workload associated with development and make professional growth a more natural part of their teaching routine.

Two key questions to consider are: Can I improve, and do I want to improve? These aren’t always easy to answer honestly. If your line manager asked these questions, you might answer emphatically, but teaching is demanding enough just to maintain standards. Finding the time and energy to focus on improvement is challenging amidst the workload. So, at what cost do we pursue improvement?

These questions are essential because they tap into the motivation behind teaching and development. The valid question of “at what cost?” is a good one, and for some, the opportunity cost isn’t worth it—after all, maintaining standards can be in of itself an improvement. Unfortunately, in many schools, continued professional development (CPD) time has been reduced to additional, time-consuming tasks that have little impact. As a result, development can be seen as just another item on an already lengthy to-do list.

Formative assessment and teacher development is a match made in heaven. It provides a solid evidence bases of research for its impact and an effective tool for staff development that makes a difference.

A justified criticism of formative assessment is that it can focus too much on immediate performance, without necessarily leading to long-term learning. The distinction between performance and learning is crucial. Kirschner defines learning as a "change in long-term memory," and we know that checking for understanding in the moment doesn’t necessarily confirm long-term retention. However, if a student can’t do something now, it’s unlikely they’ll be able to do it six weeks from now. This distinction is important, and delayed assessment opportunities can provide valuable insight into whether content has been truly learned.

It’s easy to be misled into thinking that students have learned something, or conversely, to believe they haven’t when the issue is really one of retrieval rather than comprehension. To assimilate new learning, students need to connect it to their existing understanding—their schema.

Consider some of David Ausubel’s work on meaningful learning, summarised as:

We know that assessing students’ starting points is invaluable for ensuring that new learning is retained. There is much more to explore about how learning happens, but that isn’t the focus of this post. If you’re interested in learning more, I highly recommend "How Learning Happens" by Kirschner and Hendrick (2020).

Formative assessment remains one of the most powerful tools for improving student outcomes. While new trends in teaching may come and go, the tried-and-tested methods of formative assessment, when combined with effective teacher development, are a clear leverage point for school improvement. By focusing on short-cycle assessments and engaging teachers in continuous professional growth, schools can create environments where both teachers and students thrive.

If you’re interested in exploring how formative assessment can transform teaching and learning in your school, I’d be happy to share more about the Embedding Formative Assessment Programme. Feel free to reach out via email to discuss how this program can support your school’s goals.

Black, P., & Wiliam, D. (1998). Assessment and classroom learning. Assessment in Education, 5, 7-74. doi:10.1080/0969595980050102

Embedding Formative Assessment. Practical Techniques for the Classroom. Dylan Wiliam and Siobhan Leahy. (2011).

Natriello, G. (1987) The Impact of Evaluation Processes on Students. Educational Psychologist, 22, 155-175. https://doi.org/10.1207/s15326985ep2202_4

Ausubel, D. P. (1968). Educational psychology. A cognitive view. New York: Holt, Rinehart and Winston, Inc.