With that infectious grin, four-year-old McKenzie Dunkley looks like any cheeky four-year-old.

But it’s the skull and crossbones on his top that teachers might claim gives a bigger clue as to his character.

McKenzie has just become one of the youngest children in Britain to be expelled from school, thrown out weeks after starting for constantly disrupting classes and attacking teachers.

In one incident he is said to have lashed out at a teacher after he was dragged away from light switches he was repeatedly flicking on and off.

Another claims McKenzie kicked her after he got into an argument with a pupil over a jigsaw.

Up to a dozen five-year-olds have been given their marching orders from schools but McKenzie is one of the first four-year-olds to be expelled.

He was sent home from his reception class on four separate occasions by the head at the Sacred Heart Primary School in Ashton-on-Ribble, Lancashire, before finally being thrown out a week ago.

His parents had refused to agree to a special action plan to deal with his behaviour.

They say he is a lively and lovable little boy who never caused any problems before starting school in September.

Now they are worried he will find it difficult to settle in a new school.

 His mother, Shelley Dunkley, 27, said: ‘They are making him out to be a thug and I think they are treating him far too old.

‘They are saying he won’t listen, is disruptive and is just doing what he wants but he’s still only four and getting used to school and they just don’t know how to be with him.

‘There is absolutely nothing wrong with McKenzie and he knows the difference between right and wrong.

‘At home he is quiet and if he does get a bit boisterous then he gets told off and told to behave himself.’

Mrs Dunkley, who is married to Mark, 33, a civil engineer, added: ‘He was one of the youngest in the class and it is down to the teachers to help him settle and I don’t think that has been done.

‘They are saying he’s very violent and all the other kids are scared of him. I’ve never heard such nonsense.’

Under education guidelines, children who behave badly can be sent home from school by the head for a fixed period or permanently.

‘They are saying he is very violent and all the other kids are scared of him’

But Mrs Dunkley, a caterer, said she was ‘shocked’ when she was called out of work to collect her son from the school.

‘They said he is being disruptive and he is very immature, but he is only four years old for goodness sake,’ she added.

McKenzie was kicked out after what teachers described as a catalogue of problems.

Head Carol Seagraves said: ‘It is only on very rare occasions that a school would consider permanently excluding a child as young as four.

‘At such a young age, behaviour of the kind that could lead to exclusion needs to be investigated and dealt with quickly by the appropriate specialists.

‘In order to do this, we do, of course, need the full co-operation of the family so that we can put the right support in place.

  ‘Our aim is not to punish but to carry out an assessment and successfully reintegrate the child into mainstream school as quickly as possible.’

She added: ‘When children are excluded permanently, if parents disagree with the decision, the usual course is for them to appeal to the school governors and then to an independent panel. Both have the power to overturn the decision.’

A spokesman for the National Association of Headteachers said: ‘Fixed-term exclusions for a four-year-old are highly unusual but they demonstrate the seriousness of the problems with this child.’

The youngest pupil to be expelled from a British school was a girl of three who was thrown out for violent behaviour.

The unnamed child was sent home for assaulting a fellow student at a primary school in Caerphilly in Wales last year.