Well it seems like your child may be struggling with ADHD that is Attention Deficit Hyperactivity Disorder which is characterised by such traits of extreme impulsivity, poor attention span and concentration and over activity which together cause hindrance in the performance of the child and that is one reason why he is trailing his peers in studies.
So he should be evaluated and managed by a child psychiatrist and with the use of ADHD medications and appropriate behavioural therapy he shall be able to overcome this condition and is is just the right age to start him on this treatment so that this adhd does not latch onto him into his adulthood.
Apart from seeing a child psychiatrist you should also consult an audiologist or ent specialist for his partial deafness provide if that has not been already done by you.
Some very good medications for adhd are adder all xr , ritalin, focalin xr, concerta, atomoxetine, modafinil, etc , you may discuss me with his psychiatrist and he / she shall choose any one of these to help him with his adhd.
Also do not get worked up and use punitive methods as it is an underlying cause which makes him to behave this particular way, have empathy for him and support him emotionally and morally.
I hope this helps.
Wish you and your son all the best.
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