* Thinking skills usually refer to higher-order thinking skills. These are not involved in learning to recite the kings and queens of Britain; they are if you devise your own mnemonic to help you remember them
* Thinking skills guru Edward de Bono has written 62 books on the subject
* Some psychologists say certain thinking skills - such as abstract thought - can't be acquired until 12. They also believe the brain reaches maturity around 16; it can be difficult to acquire new thinking processes after that
* Metacognition - which occurs when someone becomes aware of their own thinking processes - is considered central to almost any thinking skills programme
Plato and the Greeks knew all about it. The French know all about it now as it's been part of their curriculum for years. Thinking. That thing we do all the time. But do we do it properly? Learning to teach thinking skills has been made part of initial teacher training, and some schools have changed their whole programme of teaching to create opportunities for using thinking tools. Yet there's still no consensus about what thinking skills are, how they should be taught, or even if they're worth teaching in the first place. Are thinking skills a gimmick, a buzz phrase, just another initiative? Or are they the basis for an educational revolution that will change the way we teach and learn?
What are thinking skills ?
Any use of the brain is a form of thinking, but when people talk about thinking skills they are usually referring to higher-order thinking.
Higher-order thinking is when we use the brain for more than storing and retrieving factual knowledge. So, learning to reel off the kings and queens of England wouldn't involve higher-order skills, but devising a mnemonic to help you remember them would.
Broadly speaking, thinking skills fall into two categories - those rooted in philosophy, such as reasoning and logic, and those rooted in psychology, such as creative thinking and problem-solving.
But behind all thinking skills is a strong emphasis on understanding the process of learning - on knowing how rather than what. The national curriculum lists five higher-order skills pupils should develop: information processing, reasoning, enquiry, evaluation and creative thinking. But some experts recognise as many as 30 separate skills.
So are thinking skills the same as intelligence? "If intelligence is the horsepower of a car," suggests Edward de Bono, author of 62 books on the subject, "then thinking is the skill with which the car is driven."
Is it possible to teach thinking skills?
Most experts say yes. Indeed, many of them make large sums of money marketing their systems to schools - and businesses - keen to get results.
But some draw a distinction between teaching children to think and teaching them strategies that allow them to apply their thinking powers effectively.
Others would quibble over terminology.
Professor Philip Adey of the Centre for Advancement of Thinking at King's College London, prefers to talk of "accelerating cognitive development". He says: "The thinking skills described in the national curriculum are not skills, they are mental processes. You can't teach them directly. But you can create a learning environment that will stimulate their development."
Opinion is also divided over the best way of fitting thinking skills into the timetable. Some people believe thinking is best treated as a subject in its own right, but the current weight of opinion is in favour of "infusion". This entails teaching thinking skills across the curriculum, by every member of staff, as part of a whole-school approach.
"It's no good just tinkering with a few ideas in the classroom," says Guy Claxton, visiting professor of learning science at Bristol University. "You have to create a climate of learning that extends to every aspect of the school. And thinking skills are only one aspect of that; motivation and social skills are also important."
At what age can children learn thinking skills?
Any age, according to those who approach thinking skills from a philosophical standpoint. "The habits of intelligent behaviour can be acquired from birth until death," says Dr Robert Fisher of the Centre for Thinking Skills at Brunel University. "There are no magic thresholds; it's ongoing, and the sooner you start the better."
But cognitive psychologists focus on two particular stages of development when the brain undergoes growth spurts: between the ages of six and eight, and again between 12 and 14. They argue that these are the key times for cognitive intervention to take place. They also believe that some thinking skills - such as abstract thought - cannot be acquired until the second stage of development, and that after the brain reaches maturity around 16, acquiring new thinking processes can be difficult.
Can teaching thinking skills improve results?
It seems likely. The main body of evidence is centred on Case (cognitive acceleration through science education), a programme of teaching science through a thinking skills approach developed by a team at King's College London. The latest evidence shows that schools teaching the Case programme at key stage 3 go on to achieve 19 per cent more A-C grades in GCSE science than similar control schools that use traditional methods. Significantly, the Case students also achieve 16 per cent more A-Cs in English, and 15 per cent more in maths, suggesting that pupils have successfully transferred their thinking skills to other subjects.
But the benefits of teaching thinking skills go far beyond improved exam performance; our exam system tends to test knowledge rather than thought processes. "Our enquiry curriculum has transformed the school," says Sue Eagle, head of Tuckswood first school in Norwich, where thinking skills have been integral to teaching for the past eight years (see case study).
"Pupils now have a real focus on learning, a spirit of enquiry, and a higher sense of self-esteem. Behaviour has improved and the school council operates effectively, all because the children can think for themselves."
Brain-based learning It's not just thinking skills that teachers are being encouraged to explore. Many experts want us to look not just at how we think, but at how the brain works, and create a style of teaching that takes that into account.
For example, experts often claim that the left side of the brain controls logical and analytical processes, while the right controls creative and artistic processes. Brain-friendly teaching tries to stimulate both sides, while recognising that individuals have dominant areas and learn in many ways.
Another principle of brain-based learning is that tension or fear causes the part of our brain associated with learning to switch off. This leaves the part that controls primitive instincts, such as "flight or fight", to take over. So children won't learn effectively if they aren't relaxed and at ease.
Other parts of the brain switch on only when they recognise they are about to learn something of direct personal importance. So brain-friendly lessons need a clear relevance to the pupils and a link to everyday situations.
Sceptics suggest we don't yet have sufficient understanding of the brain to devise an effective system of brain-based learning, but the enthusiasts aren't deterred. "Yes, some of it is guesswork," admits Steve Rogers of the University for the First Age, an organisation that promotes after-school brain-based activities (see resources). "But if you don't test things out, you don't move forward."
The thinking classroom Turning your classroom into a community of enquiry isn't easy. Thinking can be hard work, and making mistakes is an important part of the process.
Children must be told that getting stuck isn't a sign of laziness or stupidity, but a great opportunity to stretch their thinking muscles.
Creating a thinking classroom means giving children time to reflect before answering, and time to change their mind afterwards. Thinking classrooms may be characterised by long periods of silence, but talking also plays a key role in formulating ideas, and social learning - working in pairs or groups - can accelerate cognitive development. Above all, they are places where children ask questions as well as give answers. "It can be emotionally challenging for teachers," says Sue Eagle. "Once children start questioning, they don't stop. Life, death, the universe - nothing can be off-limits."
The thinking teacher So if you aren't there to give them the answers, what are you there for? To encourage metacognition, create cognitive conflict, and facilitate bridging, of course.
Metacognition, which occurs when someone becomes aware of their own thought processes, is considered central to almost any thinking skills programme.
You can encourage this learning about learning by always trying to make the mental processes involved in the classroom explicit, and by encouraging pupils to keep a learning log to reflect on what they've been doing.
Cognitive conflict occurs when the mind is faced with new possibilities that perhaps go beyond its current lines of reasoning. As a teacher, you have many possible ways of creating cognitive conflict - by introducing new material to a class at key times, for example, or by playing devil's advocate during debate, or by constantly asking pupils to define terms, give reasons, or expand on their initial answers.
Finally, bridging is the name given to the mental process of taking thinking skills learned in one context and applying them in another. By linking your schemes of work in such a way that children can make connections, you can help them learn to bridge.
Although it's only in the past few years that thinking skills have appeared as part of initial teacher training, Robert Fisher is convinced that many teachers have been promoting thinking skills without realising it. "They have always developed thinking skills in their pupils - it's the natural instinct of a teacher," he says. "The difference is that they are becoming more aware of what they're doing. There's a quiet revolution taking place."
So who are the chief revolutionaries?
The Department for Education and Skills and the teaching unions have both recognised that thinking skills are an invaluable part of professional development. The DfES awards best practice research scholarships, and, since 2000, the NUT has funded a series of research awards encouraging teachers to develop schemes of work that apply thinking techniques within specific subject areas.
Projects have included the piloting of Came - a cognitive acceleration programme similar to Case but focusing on maths - and the use of thinking skills to tackle motivation problems and underachievement, particularly in boys.
"It's given the teachers a tremendous lift," says the NUT's head of education, John Bangs. "It's freed them from the straitjacket of teaching subject matter and allowed them to ask fundamental questions about the learning process."
The National College for School Leadership, meanwhile, has established several thinking skills networks, in which up to 30 schools work together to share ideas and good practice. And a growing number of local authorities have established their own initiatives. In Northumberland, thinking skills have been deemed a major priority, and several hundred teachers have received Philosophy for Children training programmes. Now demand for professional development has increased to the extent that the LEA has introduced its own "teaching thinking certificate" accredited by the University of Newcastle.
Giving the brain a workout Puzzles and games can play a key role in developing thinking skills. Word games or number games; two-minute teasers at the start of the lesson or more complex problems that may take a lesson to solve; lateral thinking or logical thinking; verbal games or physical games; tests of memory or tests of strategy. The list is endless. But the trick is to make children aware of the skills they are using as they tackle each puzzle.
Starting lessons with a puzzle or game can be a useful warm-up, but another possibility is to try some brain gym, a series of exercises and massage routines designed to increase the supply of oxygen to the brain and improve mental alertness (see resources).
Thinking tools: different hats Thinking tools is the term applied to ideas that make the acquisition of thinking skills easier. Edward de Bono developed the "six hats" method as a means of teaching people to view problems from a range of perspectives, and so develop a more rounded way of thinking. In a group of people considering a problem or proposition, one person will consider the situation analytically, another emotionally, another positively, another negatively, and another creatively. The final person tries to control the process, to "chair" the meeting. Encouraging children to try out roles makes it easier for them to understand the approaches to thinking through problems, and to become aware of their natural habits of thinking.
Thinking tools: mind-mapping "The problem with thinking is that you can't see it," says Ian Harris of training company Model Learning. "Once you make thinking visible it becomes possible to understand the processes involved." Perhaps one of the best-known thinking tools is mind-mapping (now often called concept-mapping or model-mapping), developed in the 1970s by Tony Buzan as a means of setting down information in a brain-friendly manner.
Mind-maps can be a useful tool for note-taking or revision, for thinking through a complex problem or for presenting information to others. A mind-map begins with a central idea in the middle of a page radiating out to major subheadings, then minor subheadings or individual facts. It may be helpful to encourage pupils to think of a mind-map as being like a tree, with a main trunk, several large branches, smaller branches, and twigs.
Teaching teachers to teach thinking is a huge industry, with dozens of companies offering their own thinking programmes, workshops and training packages. Some offer schemes of work, often in specific subject areas, but most tend to focus on thinking tools. Some are backed by research and evidence, but plenty aren't.
But it's hardly surprising if teachers feel in need of a helping hand, given the complexity of the issues involved, and the inability of the experts to agree on the best approach. So where to start? The best advice is probably to ask around to find which workshops or materials other schools have found useful. If you do buy in training, keep an open mind - and don't treat everything you're told as gospel. There's probably someone else out there giving very different advice.