Brief Answer:
Please get him evaluated by a pediatric psychiatrist

Detailed Answer:
Hi

Thanks for asking on this platform

I have gone through the query and do understand your concern.
A slight distraction from studies and unattentiveness in class in normal in this age group. But if it is significantly abnormal (in comparison to peer group) that too both at school and home, evaluation by a pediatric psychologist is needed.
A proper behavioral assessment can tell whether it is normal for this age or a form of Attention deficit hyperactivity disorder (ADHD) which is common in this age.
Again ADHD can be mild to severe based on the symptoms of inattentiveness and/or hyperactivity.
The symptoms of inattentiveness like not to give close attention to details or makes careless mistakes in schoolwork/work/other activities,
like difficulty sustaining attention in tasks or play activities, not listening to what is being said etc.
This may be associated with symptoms of hyperactivity like unable to sit at a place, unable to finish one action at a time etc.
Giving medications and behavioral therapy helps in such cases.

I hope this helps.
Please let me know if you have any more doubts.
Regards

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