How do you know when a social networking site isn’t cool anymore? The day that your dad joins up. A new study has found that young people are turning their backs on sites such as Facebook and Twitter. Meanwhile, the number of 35 to 54-year-olds using such sites has rocketed by 25 per cent in the last year.

So what can you do if you don’t want to be poked by your mum or added by your gran? Here’s a round up of the coolest sites and virtual worlds for children – just make sure you hide this page from your parents.

ClubPenguin.com (28 million users)
Five years ago, if someone said that penguins would soon be taking over the world, they’d be laughed all the way to the South Pole. But today, all the kids in the know use Club Penguin. When you sign up, you adopt an animated penguin to chat to friends, play games, explore, collect coins and even personalise your very own igloo. Waddle on!

Poptropica.com (76 million users)
Do you dream of travelling the world and having adventures? Poptropica could be the site for you. Your avatar moves from island to island, changing costumes and collecting a special medal every time you complete a quest.

Habbo.co.uk (135 million users)
Have you ever played Wobble Squabble? Or Battle Ball? Book a room at the biggest hotel on Earth, the Habbo, and give them a try. Use Habbo Chat to communicate with your friends and design your own space for them all to hang out.

Neopets.com (54 million users)
If you don’t have a pet but want one, or you have one but want more, you can adopt your own at Neopets. Use Neopoints to buy them food, accessories and toys and win more points by entering them into contests. Just don’t try and stroke your computer screen – it’s really not the same.

Stardoll.com (34 million users)
For hundreds of years, girls have played with dolls and dressed them up, from paper dolls to Barbie. So it’s no surprise that there is a site where you can adopt a doll and try new outfits, hairstyles and accessories. You can even give your favourite celebrities, such as Miley Cyrus and Avril Lavigne, a makeover.

MoshiMonsters.com (2 million users)
Why adopt a pet when you can have your very own monster? Your monster can roam the streets of Monstro City, solve daily puzzles to earn Rox currency, keep a Monster blog, and make friends (or terrorise) the other inhabitants.

FreeRealms.com (4 million users)
It’s only just launched, but Free Realms is already gaining a large following thanks to its addictive role playing missions. You can construct your own character, whether human or pixie, and talk to your friends on instant messaging as you play.

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