There are a number of ways to deal with this issue.
Firstly ask the following questions, is this a recent thing or has your child always had social problems?
Is there conflict in the home?
is there a new addition to the family - a new sibling, a new animal that your child feels he is not getting the attention he craves?
Is he getting quality (not necessarily quantity) attention to make him feel secure and loved?
Were you a stay- at- home Mum now gone back to work?
Are grandparents in evidence in the child's life?
Does he have other interests - does he play sport?
Is he getting adequate sleep?
Is he fit and healthy, eating balanced healthy food and not loads of "junk" foods/fast foods?
If these are all in order, then at school - has he been the victim of bullying?
Is he perhaps ADHD/ADD? Assessments with a child Psychologist or ADHD coach could help here.
A suggestion already given that if he has finished the work, then to be given extra work is a good idea, but is he actually finishing his work adequately. If this is not so, then he may need to be separated from the class for a period of time so that he has no distractions and when he completes a task well, that he is praised for it.
(Praise is also necessary at home whenever possible, even for small achievements, like taking his plate to the kitchen after supper.)
We tend to dwell on the negatives, whereas, we all need to be recognise for our positive actions too. Very much in the case of 6yr old children who are trying to deal with life issues as they are no longer babies, but not yet adolescent (that brings other issues).
a)Give him lots of encouragement, but don't accept bad behaviour, he needs to know it not "cool" to be a bully, it's more cool to have friends and make others happy.
b) Wherever possible reward him, even with a smiley face sticker on a chart on the fridge when he brings home a positive report from his teacher on his day's behaviour.
c) Spend time playing with him and model acceptable behaviour.
d) If there are issues at home, talk with him or get a councillor involved, but children are very perceptive and if you keep him in the dark, it causes great emotional problems that come out in negative behaviour.
e) Talk to him about how he feels when others hurt him, how does he feel? Then he mustn't hurt others.
f) discipline and love go together and children thrive on having boundaries that make them secure. Let your yes be yes and your no be no and he needs to know there are consequences to his actions, both the positive and the negative and what consequences does he choose to have. The teacher needs her rules that she sticks to and you do too, and don't allow him to manipulate you to break them, but let him know even though he acts badly, you still love him, but you don't like the behaviour.
I hope this is helpful.
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