For many young teachers, last week's day off school was their first taste of industrial action
Billy Bragg's hair was greyer, his face a little more weathered than when he performed at the last national teachers' strikes in 1987.
"If there's any socialism left in this country," said the lefty balladeer at the rally in London last week, "teachers are at the cutting edge."
But if Bragg's face looked older, the face of the 2008 teachers' strike was predominantly younger, fresher and significantly female.
This is a generation of teachers too young to remember the last national strikes, the pit closures and printers' clashes with police.
Some of their slogans were a little more sophisticated than "Maggie, Maggie, Maggie; out, out, out." Instead, one placard posed the question: "If an IT worker is underpaid by a third, then suffers a 12 per cent pay cut followed by cost of living rises of 2.4 per cent (against an actual 4.5 per cent inflation rate), how long before they have fair pay?"
Most of the placards were not hand painted, but bulk printed - and sometimes laminated in the school print room.
Mike Fletcher, 57, from Maria Fidelis RC Convent School in north London, took part in the 1980s strikes. "People are saying we don't have the same justification as last time, but I think we are in a very similar situation of boom and bust," he said. "I'm out marching today because I'm concerned about our younger teachers."
Unions and employers around Britain were watching closely to discover whether this new generation would embrace industrial action in the same way as their parents.
Aggie Makulska, 31, a newly qualified teacher at Benthal Primary in east London, lives with pound;30,000 of debts and her immigrant parents on a council estate. "I don't see why I should have to live like a student or a Traveller - I've done that," she told the rally.
If the 6,500 teachers who marched through central London were under any illusion that striking was a fun day out, that was quickly shattered. "Get back to work you lazy bastards," shouted a man in the doorway of Pizza Hut.
Elsewhere, the response was more sympathetic. Passing cars tooted support as teachers picketed schools in Leeds and Oxford, and City Academy in Bristol.
In Birmingham, where teachers joined with striking support staff to cancel classes in 248 schools, a white-haired maitre d' enthusiastically conducted an orchestra of 2,000 teachers as they marched past his Italian restaurant.
Sameena Khan, a 28-year-old English teacher from Swanshurst Girls' School in south Birmingham, said she could not afford to buy a house on her salary. "We're taking work home with us, working round the clock," she said. "But everything's going up in price. It's hard."
Her colleague, Janine Wulf, 37, said: "Our pay has just been eaten away, and it hurts. That affects how you see your job; how much effort you're willing to give for your job."
These teachers were all prepared to take rolling strike action, which, National Union of Teachers (NUT) sources suggested, might begin in September or earlier - if members agree.
Some of the statistics are eye-catching: about 5,000 schools shut down last Thursday, and another 4,500 sent home some year groups, according to a TES survey of 138 local authorities in England and Wales. Some 2.7 million pupils had the day off school.
What is clear is that a significant proportion of NUT staff balloted for action turned up to teach. Some could not afford to lose a day's wages; some had not voted for the strike and did not agree with it.
At the Hayesbrook School in Tonbridge, Kent, school leaders taught up to three classes at once in the school hall. Only 11 of the school's 27 NUT members chose to strike, and another 38 teachers were from other unions.
Nigel Blackburn, a co-head, said the school had put no pressure on teachers to stay in class. "But some NUT members were conscious that striking wasn't the way forward, and many had exam classes they wanted to cover." he said. "We were very fortunate that we didn't have to cancel a single class."
If there were about 150,000 NUT members who went out on strike nationwide, there would have been 300,000 teachers from the NUT and other unions who put in a full day's work last Thursday.
Ed Balls, the Schools Secretary, used that imbalance to advantage.
Visiting Wentworth Primary in Kent, he said: "The idea that lessons are being lost is very frustrating, and I'm sure I share that opinion with most teachers."
The difficulty of motivating this generation's workers to take strike action is a problem that older unionists acknowledge. Alan Taylor, 57, a teaching assistant at Fox Hollies Special School in Birmingham, persuaded many of the support staff to come out on strike in February, when Unison and other unions shut down 168 of the city's schools. But, he said, it had been far more difficult last week.
The NUT would face the same challenge in motivating teachers to join a second, third or fourth day of strike action later this year," he said.
"If the Government and Birmingham City Council think the unions are losing support, they can just sit in their offices and wait it out," Mr Taylor warned. "We're not going to get everything we're asking for, so we're going to have to sit down and compromise."
Some parents were supportive of last week's strike, but warned that their patience would run out if the strikes were repeated.
Rachel Lankester, a City PR consultant, used the day to take her 10-year-old son to Birmingham to visit her father in hospital. "I am sympathetic to teachers, but it would get increasingly difficult to support rolling strikes," she said.
As Roger King, general secretary of Birmingham NUT, packed away the banners and placards, he acknowledged the challenge of maintaining the support of both teachers and the public.
"We never expected the Government to roll over on the first day," he said. "We need to come together with other workers to force ministers to listen."
Another activist walked by with a box full of leftover leaflets, and hollered cheerfully: "See you back here in September!"