Evidence-based education

Evidence-based education is an approach to all aspects of education—from policy-making to classroom practice—where the methods used are based on significant and reliable evidence derived from experiments.^[1]

It shares with evidence-based medicine the aim: to apply the best available evidence, gained from the scientific method, to educational decision making. "Evidence-based teaching" refers to the teaching aspects.

Sources of evidence

Meta-studies of classroom-based experiments

As with the testing of new drugs, evidence-based teaching methods are derived from controlled trials. When several of these studies are compared, and their conclusions combined, we get a meta-study or meta-analysis. This is significantly more reliable than the results of individual studies due to the difficulty in controlling variables and individual bias.

Two sources of meta-analyses in education include: Visible Learning from a team in New Zealand under John Hattie^[2] and Classroom Instruction that Works from a Colorado, USA team under Robert Marzano.^[3]

The Best Evidence Encyclopedia, from Johns Hopkins University, claims to continually evaluate educational research. However, the site frequently refers to the authors' own Success for All website which was critiqued in Jonathan Kozol's book, The Shame of the Nation, as excessively dogmatic, utilitarian, and authoritarian.

According to the Marzano study, there are ten classroom methods which have been shown to work significantly better than many others:

• using analogies and similes
  • identifying similarities and differences;
• note making and summarising;
• developing a growth mindset;
• repetition and practice;
• graphical organisers and methods;
• cooperative learning;
• setting goals in advance
  • providing feedback (formative assessment);
• hypothesis testing;
• activating prior knowledge;
• advance organisers.

Although Hattie's work does not exactly mirror this list, the main reason is that the New Zealand study looks at everything related to education, including family effects and changes to the curriculum, while the Colorado study looked only at classroom methods. There are, however, no incompatibilities and most of Marzano's top-ten appear high on Hattie's list.

Hattie points out that there is no shortage of effective methods - almost anything you try in education seems to have a small beneficial effect. He therefore uses a scale of effect size which measures by how much the learning is improved. As an effect-size of 0.4 is the average for all interventions (and also the effect of a hard working, well organised and enthusiastic teacher), he suggests that methods with an effect size above 0.4 should be used as a priority. This ties with Marzano, whose list starts at an effect size of 0.59 for Advance Organisers and increases up the list.

Educational neuroscience

Educational neuroscience uses the methods and insights from the study of the brain to investigate educationally inspired questions.^[4]

The evidence derived from neuroscience now provides broad guidelines for various learning theories since, while the details have yet to be revealed, we now know some of the mechanisms underlying the learning process. The brain is now understood to perform a large number of separate processes, several of which need to work together for any given task (e.g. reading). Neuroplasticity refers to the brain's ability to adapt and change, and learning difficulties can reflect significantly weak development in one or more area so that learning is seriously impaired. A wide range of books are now available which attempt to translate the sometimes complex ideas of neuroscience into teacher-friendly language. David Sousa has a series headed by 'How the brain learns'.^[5] 'Learning and the Brain'^[6] is an excellent introduction to the subject as the authors have included only material relevant to teachers and done so in a jargon-free way using diagrams. Links to other relevant books can be found on the Evidence-Based Teachers Network website.

Myths and low effect-size methods

Myths

Neuroscience has identified a number of common beliefs (or neuromyths) which are not supported by evidence and include:

• the belief that students have Learning styles (commonly visual, auditory or kinaesthetic);
• that they may be left or right-brain dominant;
• that there are critical periods during school-years when certain learning needs to take place.

Other myths include

• the belief that students need water available at their desk to maintain hydration,
• that special diets or brain foods (rather than a balanced diet) can improve learning
• that Neuro-Linguistic Programming can help learning.
• that the start of the school day should be delayed since teenagers go to sleep and wake-up late.

Low effect size interventions

John Hattie shows that many of the interventions favoured by government in many countries have low effect-sizes, but often high cost:

• Setting or grouping by intelligence
• Retention – keeping a low achieving pupil down to retake the year
• Reducing class size (the effect is not great until the class size gets below 12)
• Charter schools and Academies – schools freed from local authority control, funded by government
• School finances
• New buildings
• Teacher subject knowledge (specialists do not get better results on average)
• E-learning, including interactive white boards (IWB), voting systems and computer suites
• Passive teaching assistants (who sit with the pupil and help them in lessons)

While all these things can show a positive effect, this is at an effect-size of around 0.2 - about the same improvement which can be achieved by partial use of some of the top-ten methods such as giving feedback, or using an advance organiser.

Effective professional development

For students' results to reflect these high effect-sizes, teachers need to develop the skills of their use. According to several studies,^[7][8] the time taken to do this lies somewhere between the learning of new facts and the development of a musical or sporting skill. While facts can be learned with a few repetitions, skills may need several hundred hours to develop. The evidence is that teachers start to become skilled with a particular method after about 10 repetitions with improvement plateauing after 6 months to 2 years of use. Continuing professional development (CPD) needs to reflect these findings. Teaching staff need the opportunity to learn about and then practice these skills. The role of CPD managers is to ensure that the time is available and the process takes place, not to instruct the teachers to follow directions. Where staff self-select their training either from external providers or from a range of sessions on a training day, they do not have the chance to develop their skills. Training, development and discussion of a smaller list of high-effect-size methods will be more effective. This process is sometimes referred to as supported experimentation or peer mentoring.

Implications for teachers

Teachers have more effect on the outcomes for their students than anyone else. The difference in outcomes for 2 teachers in the same college is significantly greater than the average of teachers in a 'good' rather than a 'weak' school. The main reason why some schools do better is that they have a higher percentage of teachers who use high effect-size methods. While individual teachers can improve their students' results using these methods in isolation, it is far more effective if they are adopted department or college-wide so that the discussions, observations and sharing-of-practice can take place easily.

References

External links

• The Evidence Based Teachers Network (EBTN)
• Institute for Effective Education (IEE)
• Best Evidence Encyclopedia