'Educators' on R4: What really matters in education

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Very interesting programme that shows we should change the way we make choices about education. The main finding from 20-year metadata study by Prof John Hattie is that the factor that has the biggest impact is teacher expertise. So much for the mantra, 'Choose the subject, not the teacher.' Things that don't really matter are class size, amount of homework, or even private/state. Also, the worst thing you can do apparently, is say 'Do your best'.

Essential listening for everyone interested in education. www.bbc.co.uk/programmes/b04dmxwl

I suppose the reason I struggle with the term 'do your best' being seen as negative is that I don't see somebody's best as a finite limitation. In my (perhaps inaccurate mind) a child who does their best will have done the best that he can on that particular day.
Given the example of the Olympics and personal bests: prior to an athlete having a new personal best he will already have a best, people improve all of the time. It's much the same as I wouldn't expect my 10 year olds best to be the same now as what it will be in 6 years time and my 10 year old would of course have his own expectation that he will improve over time.
I suppose I just don't agree that doing your best is linear and I feel that it really has a lot more to do with the amount of effort that a child puts in. A child can control their level of effort but they cannot control other aspects such as the outcome of an exam as that will be dependent on having the knowledge required to answer the questions

Yes Missunreasonable I use "do your best" for as particular moment in time, hence on exam day.

Just do your best in English as an instruction all year is not helpful if my kid feels rubbish at English. Then we need to break down what he needs to practice on to improve.

It's all too late for that on exam day hence "Do your best and there will be cake after tea!"