The Learning Engine

The Tool Formerly Known as The Spacing Calculator

It has been a while since I last wrote. Not because I’ve not been interested (although I’m a little bored of reading about AI in education) but because I’ve been focused on refining my own approach day-to-day. Most importantly, I’ve been focused on ensuring that what I do leads to good outcomes for my pupils. I’m more confident now than I have ever been that my approach works. You can read more about the results here.

These results would not have been possible without the tool I created to make systematic retrieval workable.

The Problem: Learning That Doesn’t Stick

There is a persistent problem in education which most teachers recognise but have come to accept as inevitable for a large number of pupils. We plan carefully, we explain clearly and, in the moment, pupils often understand. Yet days, weeks or months later, much of that knowledge is no longer secure. It has either disappeared entirely or it has weakened to the point where it can no longer reliably support new learning. As a result, we find ourselves revisiting pre-requisite knowledge which ‘should’ be secure, slowing down progress and, over time, lowering the ceiling of what pupils are able to achieve.

Most teachers are now familiar with the idea that retrieval matters, and that knowledge needs to be revisited over time if it is to be retained. However, there is a significant difference between understanding the importance of spaced retrieval and being able to implement it in a way that is both systematic and sustainable. To sequence retrieval effectively requires keeping track of what has been taught, deciding what should be revisited, spacing those revisits appropriately, and doing so across multiple classes. When combined with the day-to-day demands of teaching, this quickly becomes unmanageable.

At the moment, retrieval tends to be ineffective. It appears in lessons, but not with the time, frequency, precision or expectation required for pupils to learn. Many teachers will have attempted to systematise it, only to find that the administrative burden outweighs the benefit, or that the system gradually breaks down. Others will not have attempted it at all simply because they don’t know how to make it work in practice.

The Consequence: Uneven Learning

The effects of this are not evenly distributed. Where retrieval is inconsistent, learning becomes uneven, and this is often misinterpreted. Differences in retention are attributed to differences in ability, when in many cases they are better explained by differences in opportunity. Pupils who encounter more opportunities to revisit knowledge, whether in school or at home, are more likely to retain it. Those who do not are more likely to forget. The organisation of retrieval is, therefore, a significant factor in pupil outcomes. Where it is weak, existing gaps widen exponentially.

The Solution: The Learning Engine

What has been missing is not awareness, but a workable system. Traditional curriculum plans provide an outline of what is to be taught, but they do not track what has actually been learned, nor do they support the ongoing and adaptive organisation of retrieval. They function like maps.

This is where the idea of The Learning Engine comes from. In many ways, education already has the visible components of a functioning system: the chassis, the wheels, the map. We know broadly where we are going, and we have structures in place to support that journey. But without something that ensures pupils are actually learning and retaining what is taught, the system does not move. The journey never begins. The engine is not the curriculum itself, but the mechanism that drives learning forward over time.

The Learning Engine, the tool formerly known as the Spacing Calculator, has been developed to address this problem. Significant updates make it easier to use and more complete. It is not a curriculum or a pedagogy. It is a tool that manages the adaptive and expanding sequencing of retrieval over time and presents it in a clear and easy to use way for teachers.

It can be used with a detailed breakdown of content or with a more general scheme of work, but crucially it does not require either to get started. Teachers can simply input what they are teaching, lesson by lesson, and the system will build around that. What matters is that it provides a structure within which retrieval can be organised effectively over time and with very little input from the teacher.

The principles on which The Learning Engine is based are simple.

· Learning becomes more durable after retrieval. Each time knowledge is retrieved, the interval (the time between retrievals) can expand.

· For knowledge to become stable and long lasting many retrievals are required. I wouldn’t like to put a number on it. Certainly more than 3 (which is an optimistic average for the number of opportunities for retrieval that most pupils are given for any piece of knowledge). I’m aiming for 10-15 retrievals per key piece of knowledge across a year.

· Retrieval should be given priority over new learning. What is the point in coverage if nothing sticks? When knowledge sticks, it compounds.

How It Works in Practice

Its use is deliberately straightforward. Input: lesson dates for a given class, a list of knowledge to be taught, the date the knowledge was initially taught and any knowledge that was successfully retrieved day to day. Output: a dashboard outlining a clear list of what should be retrieved and taught in each lesson. As The Learning Engine is maintained (with less than 30 seconds of input per day) retrieval schedules update automatically. Where retrieval is not successful, it is not recorded as complete, and teachers retain the professional responsibility to address the underlying misconception and update the teaching list accordingly.

The role of the teacher within this remains central. The Learning Engine does not determine how content is explained, which examples are used, or how misconceptions are addressed. It does not replace judgement. Rather, it removes the need to manage the complex and menial task of scheduling that is required for effective retrieval, allowing teachers to focus on the quality of instruction itself. It acts as a form of infrastructure, supporting the consistent application of principles that are otherwise difficult to sustain.

A Shift in Emphasis

Over time, systematic spaced retrieval leads to a clearer understanding of what pupils know, and a greater likelihood that what is taught will be retained. It does not rely on changes in effort or motivation, but on improving the organisation of learning . In doing so, it addresses a problem that has long been recognised but rarely solved in a way that is both practical and scalable.

The Learning Engine will be released as a free download later this week, alongside a detailed guide on exactly how to use the system and a ‘taster’ teaching list you can use immediately. Everyone can start using the tool straightaway. It can be used to ensure learning in any subject, in any context (even outside of formal education), and does not require a pre-built curriculum or any particular means of encoding. Teachers can begin from wherever they currently are, with whatever they are already teaching.

We have spent decades refining explanations, modelling and curriculum design. Retrieval has received far less attention. The Learning Engine is built on a simple premise: that the most significant gains in education are now likely to come not from improving how we present knowledge but how effectively we retrieve it. Retrievalism reflects a shift in emphasis. The Learning Engine makes systematic retrieval precise, manageable and reliable, and will be available for everyone to use soon.