Britain's Prince Harry (search) will spend his 21st birthday Thursday in the sober setting of his military academy but says he has no plans to tone down his wild child image.

"I am who I am and I'm not going to change," Harry said in a round of interviews with news organizations ahead of his birthday.

Royal watchers, however, predict the milestone may mark the maturing of the royal family's most wayward son.

Flame-haired Harry has long been regarded as the wilder of Prince Charles (search) and the late Princess Diana's (search) two sons, a reputation that's been bolstered by stories of marijuana use, underage drinking and an early morning scuffle with a paparazzi photographer outside a London nightclub.

Harry frequently appears in the pages of Britain's tabloid newspapers with a cigarette or can of beer in hand and made headlines this year when he chose a Nazi uniform and swastika armband for a costume party.

Speaking to journalists at his father's farm in Gloucestershire, southern England, the young prince said he has grown up in the past few years but still has a "child streak" he is in no hurry to lose.

Royal watchers have credited Harry's blooming maturity to his enrollment at the prestigious Sandhurst military academy in May, a program which included a grueling five-week induction.

"I think he's buckled under to the team spirit of being a cavalry officer. I imagine he's had to grow up pretty quickly," said Cathy Brooks-Baker of Burke's Peerage, a publishing company that specializes in the royal family.

Harry said during the intensive induction he had received the same treatment as fellow officers, including being yelled at by superiors and "treated like a piece of dirt." But he said he was relishing his officer cadet training course.

"I do enjoy running down a ditch full of mud, firing bullets. It's the way I am. I love it."

Ingrid Seward, editor in chief of Majesty Magazine, said the army experience had provided Harry with the self-discipline he needed.

"I think that experience would mature anyone," Seward said.

Harry's lack of maturity was cited by many who criticized his wearing a Nazi uniform at a January party.

"Maybe it was a sign of my own immaturity," Harry said. "I'm becoming 21 ... something like that I will never do again. It was a very stupid thing to do and I've learnt my lesson.

Brooks-Baker suggested that the marriage of Harry's father to his longtime partner Camilla Parker-Bowles this year helped tame the younger royal.

"I think the fact that he now has a stepmother who probably is very kind to him is a settling factor," Brooks Baker said. "She has a son of her own so knows how to handle him and that will have given him a certain grounding."

Harry said Camilla had always been close to him and his older brother William, 23, and he enjoyed her company.

"She's a wonderful woman and she's made our father very, very happy which is the most important thing. William and I love her to bits," Harry said.

Harry refused to be drawn on his own relationship with Zimbabwean Chelsy Davy, 19, saying only that she was "special" and "amazing."

The young royal said he was keen to do more charitable works, including in Africa, where he worked with AIDS orphans during a break in his studies last year.

"I'm not going to be some person in the royal family who just finds a lame excuse to go abroad and do all sorts of sunny holidays and whatever," he said.

Harry has decided not to have an extravagant birthday bash, like his brother William's fancy dress African-themed party at Windsor Castle in 2003.

"I didn't feel like one just because I've got other things to think about, more important things to concentrate on," Harry said.