A year ago, I gave up the corridors of power - writing speeches and devising strategy for Tony Blair - for the noisier corridors of an improving inner-city school: Islington Green in north London. These are 10 things I’ve learned.

1. There is no place more stimulating than a school. Here speaks the new boy. A teacher of 20 might say “exhausting” rather than “stimulating”. For me, being out of meetings and in the playground, classroom, and canteen talking to naive, anxious, rude, inquisitive, funny, students was exhilarating.

2. The politician-teacher relationship must become more equal. The battle between government and media for the political agenda puts a premium on “momentum politics” - if you are not active, you are accused of drifting.

If you don’t break a few eggs, you are deemed to be soft on reform. Yet what is required on the front line is consistency, partnership and freedom to innovate. It’s time politicians showed more humility and worked with teachers as genuine partners - valuing practical and creative implementation as highly as policy formulation.

3. Authority comes from consistency. I’ve spent a lot of time in the last year trying to work out what gives a teacher authority. How is it that pupils know instantly that I am an unqualified teacher? One child humiliatingly asked early on - “Sir, why aren’t you strict like the other teachers?” The nearest answer I got was consistency. Pupils knew from some teachers that when they said something or threatened a punishment they would always carry out the threat, so it was not worth messing with them.

4. Pace and planning make a good lesson. I’ve watched many inspirational lessons at Islington Green. The common ingredients are meticulous planning and pace. I learned that each 10 minutes has to be planned in detail. Each has pace and variety to keep the students challenged and occupied. I too often made the mistake of running out of material 20 minutes in and floundering for the next 40.

5. The transition from primary to secondary is still not right. Why is it that some of the most challenging students sit quietly and calmly in primary school but as soon as those same children are in a secondary school they act completely differently? Government and teachers have been wrestling with this issue for years. The key stage 3 strategy has had some effect focusing on literacy and behaviour. But we haven’t got it right yet.

Our school is segregating Year 7 - with different lunch and break times - and fewer disruptive room changes. Government needs to allow schools greater flexibility.

6. The biggest inequality is between the literate and illiterate worlds.

I’ve been struck by the gulf between the world of politics where words are crafted, analysed, debated, and the world of schools like mine where four out of ten join with a reading age below nine. How can these students become engaged citizens without the tools of communication? The literacy strategy has clearly had a big impact. But there are still large numbers - concentrated in some schools - who have not got the basics. I have learned from teachers the sort of remedies that might work. There should be literacy centres off-site where students could be sent for a month’s intensive literacy work. Students need summer schools between Years 6 and 7 dedicated to literacy. There is a strong case for doing more on oracy - speaking, not just reading and writing, so that all students can communicate effectively in something other than street slang. This has been neglected for too long.

7. Keep investing. More money is coming into school, no question. In Islington alone we are getting nearly pound;130 million to rebuild all secondary schools. But I can see daily the need for more resources - to cut class sizes, to pay for more teachers so that some of the best teachers can work with pupils in small groups. The Government should not be fazed by those calling for tax cuts. It should pledge that education is the number one priority for extra resources if Labour gets a third term.

8. All schools with good heads, not just academies, should get greater freedom. Academies can provide a welcome source of innovation, but the Government should move quickly to give all heads who are doing well, equivalent freedom.

9. There are no magic bullets. I was a great advocate of the big symbolic policy but now I can see that effective delivery is about the hundreds of small, repeated, systematic interventions between teacher and pupil. If there is a magic bullet, it’s the headteacher. He or she makes more difference than any government policy. Get a good head and everything flows from that - good ethos, motivated teachers, a learning environment.

Government initiatives, applying as they do to 4,000 secondary schools each at a different stage of reform, will work better in some schools than others. I’ve seen myself that what matters is how the head - Trevor Averre-Beeson - tailors policy for the needs of his school.

10. Teaching makes you hungry. I have a new ritual every break time: the staff-room snack queue. A long, snaking line of ravenous teachers awaiting their turn to buy large slices of pizza, sausage rolls or Kit-Kats - “I can’t teach without one”, as one teacher put it. I have been struck perhaps most of all by the physical and emotional energy needed to teach lesson after lesson, day after day - it is a highly rewarding but tiring profession.

Peter Hyman’s book, 1 out of 10, from Downing Street vision to classroom reality, is published by Vintage, pound;7.99