At boston's high-achieving charter schools, the teaching is lively, the staff are bright-eyed and the pupils, mostly from deprived inner-city backgrounds, are impeccably behaved.
Since the 1980s, the charter school movement in America has allowed independent education providers to spend public money schooling children in the hope that they can succeed where state-run schools have failed.
Today, there are more than 3,000 charter schools in the United States, some run by profit-making companies, others set up by universities or educationists who think they can do better than the state.
Although the Conservatives want to introduce similar schools to England, their record is mixed. This summer, a Stanford University study showed that 37 per cent of charter schools were giving pupils a "significantly worse" education than standard state schools. Only 17 per cent of them delivered a better education, and 46 per cent made little or no difference, the study said.
But some deliver success impressively. Last year, Roxbury, a middle school which serves some of Boston's most deprived neighbourhoods and is housed on the third storey of a nursing home, out-performed nearly 80 per cent of middle schools in the entire state of Massachusetts, one of the most prosperous in the US.
At Excel Academy in East Boston, a 10-14 middle school, pupils outperformed their local and state peers at all grades in 2008 in the English, maths and science tests taken by pupils in every publicly funded Massachusetts school. This is despite the fact that three-quarters of Excel pupils qualify for free or reduced school dinners, and 69 per cent are Hispanic - the most underachieving group in Boston.
Excel teachers hold their pupils' attention completely, delivering pacey, carefully-structured lessons. Activities like "mad minute", where pupils have 60 seconds to write everything they can on a subject, break an hour up into short bursts that do not give the class an opportunity to become bored.
But what really stands out are the routines established in these charter schools that underpin all lessons, to help maintain order and achieve consistency. Teachers expect pupils to SLANT: Sit up straight, Lean forward, Ask questions, Note key information and Track the speaker. Or to DEAR: Drop Everything And Read.
At Excel, a distinctive clicking sound can be heard. It punctuates otherwise silent classrooms and comes over in waves during circle time. "Let's hear some snaps," says the principal, and pupils begin, as one, to "click" their fingers. It is a way for them to show their enthusiasm or appreciation, without disrupting a lesson by calling out.
All are uncompromising when it comes to discipline and behaviour. "We believe if we make a big deal about the small things, we can stop the big things from happening," says Kyra Wilson Cook, director of dissemination at Roxbury.
If tight discipline is one charter school essential, long hours are another. The school day can run from 8.30am to 5pm. Many pupils stay even later for clubs, sports or extra help and some even come in at weekends, despite facing daily commutes of up to two hours. This culture allows more learning but places an extra burden on staff as well as pupils.
The first thing you notice about Komal Bhasin, the Excel Academy head, is her age: she is just 28. The Harvard graduate sounds slightly miffed at the suggestion that an average teacher age of 30 is the secret to her school's success. It is about quality, she insists, not age.
But even if it is not a pre-requisite, youthful energy must help teachers in charter schools cope with long days, average salaries of around pound;25,000 less than in conventional state schools and little job security.
Unlike their colleagues in the conventional American state school sector, charter school teachers do not enjoy tenure. At Excel, one-year contracts are standard; in the past, the school has not blanched at laying off its entire staff in the summer and starting again from scratch.
But is it replicable elsewhere? Natacha Meyer, a science teacher at Roxbury, admits: "No. This model requires teachers that are incredibly dedicated. I don't think it works for all teachers. But it does work for all students."
It isn't just the short-term contracts, long hours and low pay that are at issue. The level of lesson observation would give the average British teaching union official a heart attack. In a previous job in a conventional Boston state school, Ms Meyer received feedback on her teaching once a year. At Roxbury, she was assessed 25 times in eight weeks.
At Excel, Mrs Bhasin has even created a new phrase to describe it. "Deprivatisation of practice is a good thing," she says.
But success, where it is achieved, can take a long time. Excel needed two years of false starts to get to where it is today.