The Pulp singer returns to the City school in Sheffield to speak to students … and return some overdue library books guardian.co.uk

Anyone trying to spot the pop star in a Sheffield comprehensive school staff room 10 days ago would have been unlikely to choose the lanky, middle-aged man in a tweed jacket and thick spectacles. Even back in the 90s, when Jarvis Cocker was the star of the Britpop band Pulp, everyone used to say he looked like a geography teacher – and he certainly looks less like a pop star than some of the teachers crowding round him in the staff room.

Cocker had returned to his old school to launch his book, Mother, Brother, Lover – a compilation of song lyrics spanning 30 years. In the assembly hall he stood on the stage where Pulp – then a bunch of schoolmates he'd harangued into forming a band – performed their very first gig in 1978. Because the band was his idea, he explained, he had been lumbered with writing the lyrics, and he sang a pretty dreadful early example – "She said, To be or not to be? Shakespeare rock, Shakespeare roll. Shakespeare rock, Shakespeare roll." A hall full of teenagers tittered with embarrassment.

Writing songs, he agreed, can be embarrassing. "So you either try to make people laugh, and make out you don't really mean it – or you try to sum up the entire universe in a single song." But all you really need to do, he said, is write about your own experience. The everyday lives of Sheffield schoolchildren are just as rich and interesting as anything they see on TV or get off the internet. "And that's my main message, really. Don't think that the things around you don't count, because they do."

Afterwards, staff queued up with their old Pulp CDs for him to sign. One had an original copy of the Sorted for E's and Wizz hit single, whose infamous sleeve featured instructions on how to fold a wrap to keep drugs in. I'd clean forgotten Cocker was once the voice of youth drug culture – and I suspect the kids he'd just addressed would be astonished – for these days he's more like the heir to Alan Bennett. He has curated a cultural festival at the Southbank Centre, made field recordings for the National Trust, appeared on Question Time, hosted a Channel 4 arts series, and currently presents an unusually cerebral Sunday show on BBC's 6 Music, whose recent escape from closure owed much to Cocker's advocacy. This summer Pulp reformed to play at a few festivals, where they were received like royalty, and last week his publisher, Faber & Faber, announced his appointment as editor-at-large, confirming his quiet evolution from drug-gobbling pop star to Renaissance man of arts.

When we get on the train back to London, he looks tired. "I haven't slept for the last few nights," he admits, on account of nerves about going back to school. "I was super nervous, yeah. I'm always nervous when I perform anyway. But you know, we all regress when we go back to school – you've got lots of weird memories of school. I wasn't bullied, but it was fairly – well, a bit rough."

His smile is slow and so shy as to seem almost sly, and he speaks softly, making little eye contact. He has a habit of half rolling his eyes back as he shakes his fringe off his forehead, which I suspect is an affectation he adopted long ago to disguise awkwardness, and he still seems slightly uneasy at being interviewed. "Well it's a while since I have been," he grins – but once we start talking about his book he begins to relax.

Lyrics, he says, aren't actually all that important to songs. "Words are important to me, but a song can work and function and be a good song with words that are fairly standard. But really great lyrics can't rescue a dog of a song. I find that quite a lot now that I'm doing the radio show. I get sent quite a lot of records and if I'm on the way back from the programme sometimes there's a lyric sheet, and I'll read something and think, oh, that sounds pretty good, and I get quite excited about listening to it when I get home. And then I'll put it on and I'll be like – eurghhh."

Cocker's own lyric writing has always been anchored in the narrative of his everyday life, finding wit and drama in the mundane details of an overheard conversation, say, or a rainy bus ride. But pop has moved on a long way since Pulp's 1995 hit Common People – the mocking tale of a rich girl who enjoys pretending to be poor – became what music critics like to call the anthem of the Britpop generation. So I show him the lyrics of the current top three singles, to see what he makes of this generation's.

"Oh, I wouldn't even know what they were," he says at once, apologetically. "I feel bad, because I used to be right into the charts. I stopped when it got too predictable. They killed it when they discovered that formula, where a single would be half price in the week that it was released, so all singles started selling loads in the first week and then dropping off. It stops that thing of a record building – the first week was always the highest – and then it wasn't interesting at all. It's a good picture of what capitalism does. They find a formula that kills off the thing they're trying to make money out of." Does he apply the same rule to – and I was going to say "technology", thinking of iPods and illegal downloading, but he interrupts softly. "Everything. It's what capitalism does to everything."

I show him the first lyric sheet – Loca People by Sak Noel, featuring a comic mixture of Spanish and profanity. "So this is No 1, is it? Right." He scans the page. "That's pretty good actually. It's kind of funny. I'd say it was vaguely educational, cos you pick up a little bit of Spanish." Next up is Moves Like Jagger, by Maroon Five.

"As a title it's OK, but that's the only interesting thing in the lyrics, I would say. Maybe they work with the song, but it's all those words – nice, smile, right. There are just certain song words that just work nicely in songs, like heart and stars, they just kind of sound right. So it's just like a list of all those words put together, with a swear word and a reasonable title." He slides it back across the table and grins. "Must try harder."

Has he heard of the next one, Iris by Goo Goo Dolls? He gives a blank look, has a read, and shakes his head in despair. "I wouldn't be surprised if that had been written by a lyrics generator on the internet or something like that. 'You bleed just to know you're alive'? I mean, really."

Cocker says he began writing bittersweet songs in his teens about awkwardness and disappointment because he wanted his life to have a soundtrack he could relate to. His own inept romantic disasters bore little resemblance to the saccharine love songs of commercial pop – so he wrote his own. I could be wrong, but his teenage audience in Sheffield didn't look to me like they were any more sophisticated than the adolescent Cocker – but judging from the charts, they don't seem to want the sort of songs he longed for at their age. Why does he think they prefer boastful rappers talking rubbish about bling, to lyrics they might actually relate to?

'Well, I've thought about that, you know. And maybe they just get that from somewhere else," he says mildly. "In a way it doesn't matter where it comes from, does it? You probably get it off Facebook now or something, I don't know. To look for some kind of insight or meaning in pop songs is not really – well there's plenty of other places where you should probably look first before you start looking for it in a pop song. I guess it was just because I was really into music as a child, and I wanted it to say more. It was the thing, wasn't it? And now it isn't.

"Music's changed in that way. People still listen to it, but it's not as central, it's more like a scented candle. It sets the mood. Also, because people like to multitask, in a way if you've got a bit of music on in the background and the lyrical content is making you want to listen to it, then that would probably put you off the texting you wanted to do. I think people like things that just make that right kind of noise, but leave your brain free to do something else."

He offers this without any hint of regret – but I get the feeling that's only because he doesn't want to appear judgmental. "I can't operate that way at all, no," he concedes. "I can't even go in pubs that have TVs on, it's horrible."

What he did share with today's teenagers was a longing for fame. Born into a lower-middle-class family in 1963, he was the archetypal arty misfit – insecure, shortsighted, "a little bit different". As is so often the way, he thought becoming famous would be the solution, and pursued that dream throughout the 80s, but after 10 years Pulp was still just a jobbing Yorkshire band with a modest cult following. He gave up, moved to London to study film at St Martins – and suddenly began writing better songs. Britpop came along, by 1995 Pulp were headlining Glastonbury and Cocker was a superstar – at which point he quickly discovered he didn't like being famous at all. After a few years of the usual cliches – groupies and cocaine, chatshows and excess – creative inspiration dried up, and in 2002 the band called it a day.

I ask why he thinks his own particular childhood longing for fame has become the universal ambition of almost every teenager today. Does it mean that all youngsters now feel as he did then – inadequate and insignificant?

"I think basically becoming famous has taken the place of going to heaven in modern society, hasn't it? That's the place where your dreams will come true. It's an act of faith now; they think that's going to sort things out." When he talked to the children he contrasted X Factor's fantasy of overnight stardom with the 15 years' work it took Pulp to be successful – but presumably he too must have heard cautionary tales about the false promise of celebrity when he was a child. So why didn't he heed them?

"Ah," he smiles, "I think everybody always thinks they're cleverer than everyone else, and they wouldn't fall into those traps."

The likelihood of any child at his old school getting the chance to find out for themselves is in reality, of course, remote – far more so than when Cocker was a pupil. Experimental bands such as Pulp were the product of a particular era when aspiring musicians could go on the dole, live in a council flat, study for free at art school, and develop their craft. Has that path now closed for good?

"Well, I hope not. But going to St Martins – if I hadn't gone there we probably wouldn't have turned into the band we did. I really think the art schools won't survive now – nobody's going to pay 30 grand just on spec, and I think there really needs to be a concerted effort to make them exempt from the fees, because basically a lot of people who would've gone won't now. So yeah, sometimes you do feel like a dinosaur, cos you've come through a system that doesn't exist any more, and that's kind of why I wanted to go and talk at the school, I suppose. I'm not meaning in a real ale kind of Keep Music Live way, I'm not really bothered about that. What I'm saying is it just stops creativity coming from that kind of background. I actually think that background has more vitality."

Compared with? "Well it has changed now. The big rock bands now are from slightly monied or privileged backgrounds." It seems to me he's right about that. "I don't want to turn it all into a class war thing," he says quickly. "Maybe they've got more to prove. Maybe they think, I've got to prove I'm not just a well-to-do toff. So I've got to create something." Or maybe, I suggest, they're now the only ones who can afford to have a go.

"Well that's why I'm glad I went to the school today, cos you can get into that grumpy old man mindset – everything's fucked, it's not like it was in my day, or whatever. But you know, in my day I was on the dole – so what kind of day was that, really? Let's not forget, the 80s in Sheffield were fucking awful – certainly not halcyon days. You can get into that thing of everything's going downhill. You know, it's not like everything is irredeemably, irretrievably fucked. I think it's good to realise that, you know?"

There was a time when it looked as if Cocker's life might be going if not quite downhill then adrift. After Pulp he married a French stylist, Camille Bidault-Waddington, moved to Paris and had a son, Albert, now eight, and tried to recover a sense of normality and anonymity. At 40 he had decided he was too old to perform – but then worried that he wasn't much use at anything else – so he released some solo records, but they weren't terribly good, and in 2009 his marriage ended. He now divides his time between Paris and London, and is gradually getting accustomed to his new public identity as a national treasure.

"Well it's nice that people say that," he says, smiling gently. "It does make you sound as if you need dusting, but it would be worse if I was called a national disgrace."

Some did call him a national disgrace when he invaded the stage at the Brit awards in 1996, in protest at Michael Jackson's messianic performance. And in truth, I was never that keen on art school pop stars myself back then. I found them a bit pretentious; too arch and fey for their own good. If I'd had any idea they'd be displaced by the cynical Muzak which passes for pop nowadays, I'd have felt very differently, and I find myself desperately hoping his words had an impact on the children at his old school.

At the end of his talk there, he took questions. "What famous people have you met?" a boy called out. Quite a lot, said Cocker – why not name some, and I'll tell you if I've met them? The boy thought for a second, and called out the first name he could think of.

"Have you met Simon Cowell?"

• This article was amended on 17 October 2011. Statistics about the changing proportion of chart artists who were privately educated have been removed because they were drawn from an informal study. The first paragraph was also modified to correct the date the interview took place.