They can be naughty, funny or adorable, but one thing is for certain: four-year-olds are never dull.
In fact, these pre-schoolers are at such an interesting age that Channel 4 have brought back The Secret Life Of Four Year Olds, a series following a group of four-year-olds in nursery, with experts eavesdropping on their conversations and analysing their development as they shared beads, fought over scooters, laughed and cried.
While four-year-olds can have many behavioural traits in common, child psychologist Dr Amanda Gummer points out that - like all children - they don't develop at the same rate, and just because one has a certain ability, it doesn't mean another necessarily shares it.
However Dr Gummer, who runs the play and parenting website Fundamentally Children, says four-year-olds will often have the following traits, skills and abilities:
They usually have a vocabulary of 1,000 words.
Can count to 10 or more.
Can name at least four colours.
They watch TV for an estimated 15.5 hours a week.
One third have a TV in their bedroom.
More than a third (37%) use the internet.
One in 10 use a tablet at home
They need 10 to 12 hours of sleep every night.
Two thirds have imaginary friends.
They tell a lie about once every two hours.
Toys and Books
Children of this age love licensed characters such as Peppa Pig or Ben 10, and many will have a favourite book, show or toy that they play with repeatedly.
They can play socially and learn to take turns, which is why board games are so popular with four-year-olds.
Four-year-olds love being read to, but will often learn the story by heart and pick up a book to make it look like they’re reading ‘like a grown-up’.
In addition, psychologist Angharad Rudkin says four-year-olds have moved into the 'concrete operational stage' of cognitive development, which means that unlike younger children, they can use logic to reason.
“They are becoming more sophisticated in their thinking,” she says, “but are still quite tied to what's observable and are still fooled by appearances.”
They also develop the ability to put themselves in other people's shoes somewhere between the ages of four and five years.
Rudkin says that while research shows that an element of this ability is present from very young, it becomes fully functioning around this age.
Play is essential for this age group, and predominantly involves pretending or role play involving imagining and practising social skills like negotiation and taking turns.
As children move towards the age of five, play can also become about learning new skills such as skipping and football. Most four-year-olds can hop, skip and so on, but only a minority can ride a bike without stabilisers or tie shoelaces.
Rudkin says four-year-olds are still quite rigid in their gender stereotyping - boys like blue and girls like pink, for instance. They play mostly with their own gender, and most girls are still very happy to be pink and princessy - tomboy preferences don't kick in until around six years of age.
They are becoming more able to regulate themselves by stopping themselves crying and reassuring themselves when they're feeling worried.
But they continue to be very dependent on adults to do most of the caring and comforting - they still need their mummies and daddies.
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