What is Making Fluent and Flexible Calculators (MFFC)?

MFFC is a whole-class intervention that aims to develop students’ knowledge and understanding of a range of mental calculation strategies. Focusing on foundational learning around addition and subtraction, the programme explicitly teaches a range of calculation processes to develop faster and more agile basic number work, with the aim of improving the maths attainment of Year 7 students with low-prior attainment.

The programme will be delivered to students in Year 7 alongside the Key Stage 3 curriculum and will involve 8 – 12 short teacher inputs, as well as regular 5 – 10 minute practice opportunities at least 3 times per week.

Who is leading this project?

The project is led by HFL Education, a large not-for-profit school improvement organisation which has developed the programme and will provide teacher training, support and resources.

What will this project look like in your setting?

If allocated to the intervention groupAs part of a Randomised Controlled Trial (RCT), settings will be randomised into either the intervention or control group. Settings in the intervention group will receive the programme being tested. for this trial, two teachers who teach a maths class of students with low-prior attainment will be invited to attend two online training webinars in October/​November 2025. The first will train teachers to deliver short assessments with a small number of students to gain a better understanding of their current mental calculation strategies. Using the results of these assessments and following a second training webinar, teachers will deliver a series of short teaching sessions and provide regular practice opportunities for their students to secure learning and build confidence during normal lesson time. A suite of resources is provided alongside the training to facilitate delivery of the programme.

School and maths department leads will need to facilitate the delivery of the programme, work with King’s College London to support the evaluation and commit to engaging staff in training, teaching, assessment and evaluation activities.

Both intervention and control schools need to engage in some evaluation activities during the project. This will include supporting the evaluators to carry out student assessments during the summer term 2026, as well as engaging in surveys and/​or interviews with the evaluators. Exact evaluation requirements will be set out in the information materials if you express an interest in this project.

Who can take part?

Schools must:

• Be a state-funded mainstream secondary school in England
• Have a Year 7 cohort in autumn 2025
• Within this cohort, have at least one class of students with low-prior attainment who are taught maths regularly as a group. *
• Not be taking part in any of the following EEF trials: Peer-to-peer coaching, Specialist Knowledge for Teaching Mathematics , Action Tutoring:
• Have not taken part in HFL Education’s MFFC programme by HFL Education within the last 3 years.

* Low prior attainment refers to students who have been identified as being lower attaining compared to their peers; schools can identify these groups using usual systems.

The EEF’s systematic review of Improving Mathematics in Key Stages Two and Three: Evidence Review (Hodgen et al., 2018) indicates that teaching should enable learners to develop various mental and calculation methods, and that quick, efficient retrieval of number facts is crucial for future success in mathematics. Furthermore, while fluent recall of procedures is important, teaching should also help learners understand how and when to use them. The MFFC programme aims to directly address each of these aspects.

A previous small-scale evaluation of impact by HFL Education indicated improvement in students’ accuracy and efficiency of mental maths strategies as a result of the programme. It has not been independently evaluated and would benefit from a rigorous trial.

This programme will be evaluated by King’s College London through a randomised controlled trialAn RCT is used evaluate an educational programme by assigning settings to one of two groups: the intervention group, who receive the programme or the control group, who continue with business as usual. This ensures that any differences in outcomes can be confidently attributed to the programme, providing a robust estimate of the impact and contributing to the evidence for what works in improving educational outcomes., meaning it will assess the impact of MFFC on students’ maths attainment. It will also evaluate students’ calculation efficiency and attitudes to maths.

An implementation and process evaluationAn IPE is used to understand how and why an intervention has (or has not) been successful. Data is analysed to explore programme quality, reach, adaptation and differentiation, as well as setting fidelity and responsiveness to the trial design. will be conducted alongside the impact evaluation to explore how schools implement the programme and to understand the perceived impact on teaching practices and student outcomes.