At Aaron Ramsey's secondary school in the Rhymney Valley in south Wales, Jeremy Evans smiles as he recalls the day when his star pupil was called up to Cardiff's first team. "I remember it very well," Evans, the head of PE at Ysgol Gyfun Cwm Rhymni, says. "The head of year came to me to say that he'd had a call from Cardiff City, asking the school's permission for Aaron to play on the Saturday against Hull. We had to call Aaron in from the yard and he had to go and see his head of year to explain what had happened."

As a model student who graduated from the Welsh-speaking school with 10 GCSE's and was regarded as university material, Ramsey had no reason to fear he was being summoned for a reprimand. Instead, he was about to create history. Aged 16 years and 124 days, Ramsey supplanted John Toshack as Cardiff's youngest player when he appeared as a substitute against Hull City in April 2007. His place in Cardiff's record books is recognised at the school, where photographs of Ramsey's achievements for club and country decorate the corridors and provide a source of inspiration to all.

"I use Aaron's name daily," Evans says. "He's one of those once-in-a-lifetime pupils. I think he helped us more than we helped him, to be honest, because he was so naturally talented. I've been teaching 25 years and he's head and shoulders above the best kid we've ever had."

Ramsey is still in touch with his roots. The Arsenal midfielder has returned to his old school a couple of times, including for a sportsmen's dinner to raise funds for a rugby tour to Canada (his younger brother Josh was part of the squad), and he is often spotted in Caerphilly, the town where he was brought up and which is famous for cheese as well as being the birthplace of the comedian and magician Tommy Cooper.

On Saturday, though, there will be a homecoming of a different kind. Ramsey, in the form of his life, goes back to the club where he spent eight years before joining Arsenal in 2008, at the age of 17, for £4.8m. He has faced Cardiff on Welsh soil once before, in an FA Cup tie at Ninian Park in January 2009. He also returned to Cardiff for a brief loan spell in early 2011, as part of his recovery from the horrific double fracture he suffered at Stoke City a year earlier, but this latest reunion feels different and not only because Cardiff are a Premier League club.

"Aaron's going back as one of the main men in Arsenal's team," says Chris Gunter, the Wales international who was at Cardiff's academy at the same time as Ramsey and remains close friends. "He got a few goals early on this season and he's just taken it on from there.

"If he has silenced anyone or changed people's minds, then brilliant, but I'm just pleased for him because there's nothing worse than being on a pitch in front of 30,000 people and having your leg broken. So to come back from that and get through it, as well as any criticism he was getting, is fantastic."

Ramsey's emergence as the standout player in the Premier League this season is a source of great pride for those who have known him since childhood. For Evans, the memories are not only of a supremely gifted footballer but a multitalented sportsman who excelled at everything he tried, including the shot put.

"He was a very good 800m and cross-country runner – you can see that with the way he's box to box with his football," Evans says.

"He was also Welsh Schools' pentathlon champion in year nine. He was competing against people who went to athletics clubs and trained two or three times a week, whereas Aaron was just doing it for the school, helping me out. I was astounded when he won.

"It was the hurdles, high jump, long jump, shot put and the 800m. Aaron was a strong boy – he threw a shot 10m. He was in third place going into the last event but he finished miles ahead of everyone else in the 800m. He was also a very good gymnast and an excellent rugby player, league and union. He was good at everything, basically."

One thing that nobody at the school wants to be seen doing, however, is receiving any praise for Ramsey's football development. "I taught Aaron maths for five years," Tony Wilding, who is also the school football coach, says.

"I think I can take a little bit more credit for how he did in his maths – which was very well – than how he did in his football. I can't claim any credit for his football because his natural ability was that good. He was an outstanding individual but also very unassuming. Even when he was representing Wales at 14 and playing two years above his age group, nobody knew he was playing apart from us, who took an avid interest in his development. He's very humble. I think that's the way he was brought up."

Kevin and Marlene, Ramsey's parents, were taking their eldest son back and forth to Cardiff's centre of excellence from the age of nine. Ramsey's progress was rapid and by the time he was a teenager it was obvious that Cardiff had a rare talent on their hands.

"In terms of looking at young players, some have three out of the four elements – technical, tactical, physical, mental – that you need but Aaron had all four," Lee Robinson, Cardiff's former academy manager, says. "He was such a talented boy. One of the abiding memories I have of Aaron at Cardiff is when we were playing Arsenal in the FA Youth Cup quarter-final at the Emirates in 2007.

"Aaron was still at school and he scored in the game. We lost 3-2 and Jay Simpson got a hat-trick for Arsenal. At the end Steve Bould [Arsenal's Under-18 head coach at the time] came up to me and said: 'You've got the best player on the pitch.' I think at that point I knew we had something special."

Shy and quietly spoken off the field, Ramsey came to life whenever he pulled on his boots. "The first time I saw Rambo play was against Swindon reserves, when I was coming back from injury," Darren Purse, Cardiff's former captain, says.

"Rambo was 15 years old, he had a day off school, he turned up with the worst haircut in the world and I looked at him and thought: 'Who's this kid?' Paul Wilkinson, the reserve team manager, pulled me over and said: 'Purse, watch this lad play.'

"Rambo was the best player on the pitch. He ran the show from the middle of the park. What summed it up was about two minutes before the end, when he put the ball in the top corner from 25 yards."

The only problem for Cardiff was that the top Premier League clubs were hovering and there was a real risk that Ramsey would leave for next to nothing.

"A lot of people had some positive input all the way through his Cardiff City youth years – loads of coaches," Robinson says, "but I think my biggest success with Aaron was keeping him at 16, when players have freedom of movement to go. I know he was being tracked by various Premier League clubs – he was going to Newcastle and Liverpool during half-term. Manchester United could have had him for £40,000 at 16 but they didn't think he was good enough. Not long after they wanted to buy him for £4.8m.

"It took me lots of discussions with Aaron's father and mother over about six months to get him to commit to signing for Cardiff at the age of 16, which we did on the back of the development pathway being that he would be playing in the first team sooner rather than later, as opposed to going to a Premier League youth team."

Never one to shout about his football feats, Ramsey kept a low profile, apart from when it came to his mode of transport – a lime-green Ford Fiesta, complete with a black and white chequered roof.

"That was his first car," Gunter says, smiling. "I'd moved to Tottenham, he was still at Cardiff and he came up to watch Razorlight in a gig in London. He drove up and stayed with me and I saw the car for the first time. When he moved to Arsenal he still had it. I think it lasted about a week. He didn't need to be driving that into Arsenal's training ground!"

Ramsey had a huge decision to make when weighing up whether to sign for Arsenal or Manchester United but Arsène Wenger's influence was instrumental. While Sir Alex Ferguson was away on holiday and happy to leave Mike Phelan, the assistant manager at United, to deliver the sales pitch, Wenger and Arsenal went to the trouble of laying on a private jet to fly Ramsey and his parents to Switzerland – where the manager was working as a pundit during the 2008 European Championship – to explain face to face, and in great detail, how the teenager's career would develop in north London.

While the journey over the next five years has not been without its difficulties, teachers, coaches and former team-mates all say they never doubted the ability of the 22-year-old Welshman, whom they feel privileged to have watched, worked with and played alongside.

"It has taken time but because you can come back physically from an injury, it doesn't necessarily mean you can come back [straight away] mentally," says Robinson, who remains close to Ramsey.

"It's all credit to Aaron and testament to his character but did I believe he would go on to do what he is doing now? Yes, 100%."