Numeracy for all (VSO)

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All children can achieve - a case study

Year 5 Intervention at a Peterborough UK primary school - A case study in the practical application of cognitive load theory and a mastery approach – Christopher Such

In September 2018, a project seeking to intervene in the core subject teaching of a group of twelve children was undertaken. It had been decided that the year five cohort of 60 children would be taught core subjects by three teachers – instead of two - to allow this intervention project to take place. The twelve children for the intervention group were selected as they were the lowest-performing of the cohort in measures of reading, writing and mathematics. In most cases, the children ended year four significantly below age-related expectations. The intervention project was set up to run for a full year, with the potential to run for a second year. 

The stated goal of the intervention was to allow at least half of the group to achieve age-related expectations by the end of year 6, though this was considered to be an exceptionally aspirational goal. Informal assessments at the start of year five showed that the group’s mathematical understanding, reading skills (including phonics) and basic writing skills (including letter formation and basic punctuation) were in many areas below that of the age-related expectations of year two, as defined by the English national curriculum. The majority of children in the assessment, for example, could not count past 109 without errors (with 200 being a common answer given for the next integer.) Only one was able to recall basic mathematical number facts such as number bonds to ten or the multiplication facts of the two times table. Letter formation for many of the children was inefficient and made writing a slow, laborious process. Only two could spell a majority of the ‘common exception words’ of the year two curriculum. The average reading age was between six and seven years old. In short, without significant intervention, these children were entirely unready for the year five curriculum. 

The intervention focused around a few key elements:

  • a mastery approach
  • cognitive load theory – specifically a focus on ensuring foundation skills to ensure working memory is increasingly free for higher-level tasks
  • retrieval practice
  • a research-informed approach to reading, in particular the development of reading fluency

In a usual classroom environment, many class teachers out of necessity use task-based differentiation to allow such low-achieving children to learn ‘something’ during the lesson; effectively children are given easier work while the rest of the class learn the curriculum content appropriate for their age. The aim of the intervention group was to teach at whatever pace was required – and to start the learning at wherever the first gaps appeared – and work towards the appropriate year 5 level, regardless of the extent to which this left parts of the curriculum uncovered later in the year. Effectively, this encompassed a mastery approach to learning (1). Mastery teaching was employed; every child was expected to learn all of the content, and deepening tasks were used for quicker graspers of the various concepts. A mastery approach – with every child reaching a designated standard before the whole group moved on – was employed. At the start of the year, it was expected that such an approach, while fruitful, would likely leave a significant part of the year five curriculum uncovered. In fact, the group engaged with at least 80% of the content tackled by the remainder of the year group. 

Based on the intervention teacher’s understanding of cognitive load theory, significant focus was placed on areas of learning that were deceptively simple, but that potentially forced children to expend significant cognitive resources, making the use of higher level skills much more difficult (2). For example, considerable time was invested each day into increasing handwriting fluency, practising blending and segmenting of phonemes, spelling of common words, recall of number bonds and times tables. All of these were prioritised as areas for development that needed to be mastered to free up cognitive resources for the challenges of the year five curriculum. (A child who has to think about how to form a letter – never mind how to spell a word – has far fewer cognitive resources available to consider higher-level skills such as sentence punctuation, syntax, etc.) For example, addition and subtraction facts within 20, related number facts to 100 and multiplication and division facts up to 12 x 12 were practised daily. 

In all areas of the core curriculum, retrieval practice was an embedded component of the teaching. Beyond the point of learning, children were required to retrieve and use the learning from previous lessons and previous topics at frequent intervals, with the intervals increasing in length as particular areas were mastered. Over time, this facilitated a change in the children’s mind-set as they realised that all of the learning that they undertook would be used again and again. (Previously, many of the children confessed to just “waiting” for the teacher to move on to new content. It may well have been the case that this was an adaptive strategy to being taught in classes where these children persistently lacked the pre-requisite knowledge to keep pace with their peers.) The group became aware that effort expended on new content would have consequences in subsequent lessons and increased their attention to new learning accordingly. Also, retrieval practice encouraged a willingness to ask questions and learn from mistakes; a common refrain in the face of mistakes was, “It’s fine – I’ll now know for next time.” Beyond the psychological impact of retrieval practice, there is robust evidence to suggest that such low-stakes quizzing leads to better retention over the long term (3).

The teaching of reading was undertaken daily using methods informed by evidence (4). Children read in dyadic pairs, explicitly developing their fluency in daily practice of non-fiction texts, carefully chosen to systematically develop their knowledge of the world. In addition, whole-class reading instruction explicitly aimed to develop the group’s understanding of vocabulary and syntax. Morphology and spelling instruction were also a key part of reading lessons. The teaching of strategies related to comprehension, inference and summarising were rarely employed to allow a focus on as much decoding and engagement with texts as possible. 

Over the course of the year, the outcomes for children significantly surpassed expectations. On standardised assessments, more than half reached age-related expectations in mathematics and writing, a year earlier than the originally stated target. All children significantly increased their reading speed from an average of less than 50 words per minute to an average of over 90 words per minute among the class. The four children that reached reading speeds above 110 words per minute reached age-related expectations in reading according to standardised tests. As reading research suggests, it was fluency and knowledge of language and the world that led to poor reading scores, not generic comprehension or inference skills. Crucially, across the core subjects the learning of the group was developed in such a way as to allow future teaching to be conducted on firmer foundations. 

The intervention group are now working as a group of twelve in year 6.


  1. What is Maths Mastery Teaching
  2. Cognitive load theory research that teachers really need to understand. See specifically these pages on Cognitive Load Theory
  3. Learning Versus Performance An Integrative Review 
  4. How I will teach reading this year