A pig in a poke.

If a doctor gives you a tablet for a medical condition you probably take it to help you get better. The knowledge that research teams at a pharmaceutical company have used their collective intellect to produce a drug to deal with your condition must reassure you that it is safe to do so. Trials will have been conducted to check that the product is safe for use in  the population meaning that, on the whole, the transaction between doctor and patient is a beneficial one.

Now go to a different situation. You're in a pub and complain about a medical condition to a group of friends. One of them identifies the condition as being similar to their own and proceeds to tell the group that he has just the thing for it. It was prescribed for him by his doctor and he has plenty of spare tablets. I would assume that the transaction that now takes place between patient and friend is not guaranteed to be  beneficial one. The intention is a good one as no friend would knowingly cause harm to another friend.

Final situation. A group of friends are discussing a medical condition. It is overheard by a non-qualified doctor who has a passionate interest in such things. This person has some working knowledge, having made potions and lotions themselves. But these products have all lacked the rigour that medical product testing has to go through. As such the products could do good or harm but due to the cautious nature of the non-doctor they contain nothing more active than apple cider vinegar and honey. The greatest power of this potion is the knowledge that it should do good. If taken with that in mind, the placebo effect is quite likely to be at play.

If you take a doctor's tablet then it will work irrespective of how you feel about it. The biological processes will happen when chemically instigated whether you want them to or not.  I don't doubt that the effectiveness of the drug can be influenced by your  willingness to let the drug work. But the greatest danger doesn't come from friends trying to share with you their best practice. It must come from those keen to share with others what works best for them, especially when the practice is untested.

One of the positives of twitter is that like-minded people can share their thoughts with others. However there are people keen to push their own manifesto through to others, and this is no more evident than between teachers. Some teachers on twitter like to share the passion that they have for their subject (English and Geography teachers seem particularly good at this!) Some tweeters give pointers to good resources to use in their subject. As a passionate teacher myself I always look at how I could adapt their suggestions into my own subject, Maths.

But the teachers that cause the greatest concern for me are the ones who introduce even more ways of teaching. We're not short of ways to teach. What we are short of in the UK is using that which already exists and ensuring that it is implemented to produce the results that it should be capable of producing. There must be a reason for this invention culture in the UK.

Take a minute to imagine why teachers are prepared to develop new strategies rather than just use the ones that are already available. Either the existing methods work or they don't. Or the new methods work better or they don't. But one thing is evident and that is this: Teachers that produce a stupendous amount of blog posts giving new ideas in education are doing this to achieve fame for themselves. I have seen some ridiculous posts by teachers who have a rate of blog production that suggests they are going for the "quantity not quality" title. Is there another reason that you can think of? I can't. I know how thrilling it is to have a post  viewed by people around the world. I can't deny that the chase of a 1000 views for one post is quite addictive. However I would not go so far as to produce poor quality material to achieve it.

The international teaching profession has, for the first time, got access to a superb meta-analysis of what actually works in education. The work of John Hattie (Visible Learning 2009, Visible Learning for teachers 2011 and International guide to student achievement 2013) show what factors influence the achievement outcomes of pupils in schools whilst also showing how to embed the work as a teacher. The thing is none of this is based on anything other than evidence of what works. To all those teachers who are spouting on about a new way to teach I would say this: How do you know that it is the methodology that is working rather than the placebo effect. What about the Hawthorne effect?

What teaching does not need is even more change. It requires a period of reflection about what we are actually doing in education at the moment and to what extent our actions are beneficial. Those professionals that are trying to make a name for themselves by producing mini-works of literature in the hope that people associate them with educational reform had better watch out. We have a way of finding out if your advice is successful. The implementation of untested strategies without some form of impact-analysis is not professional. Just because it sounds right doesn't mean it is right. Teachers need to look at the evidence before selecting what to do. Rather than add new things to the list of activities that teachers do, we should surely be looking at abandoning those activities that are shown not to add any additional benefit to the pupils in our school.

Those wannabe-famous teachers who aim to get their name in the staff-rooms of schools around the country through untested methods are causing more harm than good. This personality contest not only takes the energies of willing teachers in the wrong direction, it also undermines the chances that our profession can select from years of accumulated wisdom.

So next time you have a teaching need, beware those trying to sell you their name under the guise of a "new improved" method. Ask them "Where's the evidence?"