Sam is five years old and he's busy saving the world. With his school jumper tied around his neck, and his chubby arms locked in exaggerated ninja poses, he's half Mutant Turtle, half Mighty Morphin' Power Ranger. But he's 100 per cent happy. Sam was born to be a superhero.

His teacher is not so happy.

"I don't want him playing Power Rangers in the playground,"
she tells his mother, who just happens to be me. "It's not nice."

It turns out that Sam hasn't actually hurt anyone, or even threatened them. He's just running around with his jumper over his shoulders. His superpower is making funny ninja shapes with his arms and rolling noisily down a grassy bank.

But his teacher's superpower is greater. She is Super-Teacher, and her mission is to rid the school of superhero play. She wins the battle: Power Rangers are banished from the playground forever, Sam is told to play "nicely", and a little of the gloss is taken off his school day.

"That's a sad story," says American academic Gerard Jones, best-selling author of Killing Monsters: Why Children Need Fantasy, Super Heroes and Make Believe Violence. "It's a common belief that these fantasy role-playing games of being heroes are in some way dangerous – that they'll lead young children to become more violent later on. But the evidence is that the children who are most into the superhero fantasies turn out to be the most sensitive, creative kids."

In fact, the evidence is coming in thick and fast that superheroes are good for children's all-round development. They may not be the role models you would choose for your child, but it's
not your choice.

As role models go, superheroes really are pretty super. Studies show that donning a super-identity can help children develop moral values. Superhero play allows them to explore abstract ideas of good and bad, death and pain, in a safe environment. And, most importantly, pretending to be super gives children a sense of control over a world that seems scary and big.

"Of all the challenges children face, one of the biggest is their own powerlessness," says Jones. "Emotional power is at the heart of children's passion for superheroes.".

As a five-year-old, Jones's superhero was Beowulf (super power: ripping the arms off monsters). "He was a terrible role model," says Jones. "He didn't do the things we want our children's heroes to teach – he didn't discuss solutions with the group, he didn't think of the safety of others, and he didn't try to catch the monster without harming it."

But pretending to be a barbarian monster-killer gave five-year-old Gerard (a self-confessed "mamma's boy") a lovely warm feeling of being strong and invincible.

The power of a superhero alter-ego can help children deal with two tricky patches in their development. The first is fear of death: around the age of three or four, children become aware that life can be dangerous, and sometimes people die – even people you love.

"This is the age when many children are struck by a sense of dread, a sense that something bad could happen to them or their family," says Jones.

For a four-year-old, nothing soothes a nameless fear better than a good superhero fantasy. Super-beings look after other people. And whatever happens, they always bounce back.

A bit later – around the age of five – children encounter another batch of strange new feelings, when they become what psychologists call "self-monitoring".

"It's around this time that children's ethical sense kicks in," says Jones. "On top of this, they're becoming conscious of themselves as individuals with their own personalities. They realise life is supposed to be a certain way, but their impulses can sometimes pull them in different ways altogether."

Heady stuff. Imagine being just five years old and having to grapple with existential notions of good and bad and personal identity. You can see the appeal of slipping into a superhero identity, of becoming someone strong and resolute, who always knows the right thing to do.

And even if they do bash each other on the head occasionally when they're playing superheroes, that's not such a bad thing. Several studies carried out in the late '80s and early '90s showed that "rough-and-tumble" play helps children develop and maintain friendships, improve their social skills and learn to deal with their aggression.

Many parents baulk at the idea that their sweet little cherub is struggling with inner feelings of rage. But feeling angry is just part of growing up, and the best way to learn to deal with that anger is by play-fighting with friends.

Make no mistake, even at the age of four or five, children understand the difference between fantasy and reality. They may not have encountered the word "gravity", but they have thoroughly grasped its effects: they know that – sadly – they can't fly out of a three-storey window like Superman, or swing from building to building like Spidey.

They also know that in real life it would be wrong to shoot someone in the head with a laser.

Part of the appeal of Power Rangers is the comic book pratfalls and exaggerated double-takes. Children love all that that Wham! Bam! stuff.

Sadly, my son's superhero days are behind him now. Three years after his Power Ranger alter ego was banished from the playground, he's outgrown his love of all things that go Wham! and Bam! These days
he flinches if anyone gets hurt on television – he's so empathetic that he actually feels their pain. This comes as no surprise to Gerard Jones.

"The most sensitive children are often the most excited by aggressive superhero play. Creative children with big imaginations almost always
go through a monster-fighting phase," he says.

So embrace your chubby-cheeked little Power Ranger while you can. He'll be gone before you know it.


Killing Monsters: Why Children Need Fantasy, Super Hero Play, and Make-Believe Violence, by Gerard Jones, published by Basic Books, £8.99.