This kid contained by my university...?
Answers: hes retarted.
Sounds like he is rocking when he is excited or slightly coy: playing video games or tennis matches. My guess is that he is working off extra dynamism built up with the anticipation of a possible win. Either way, don't verbs about it. It doesn't sound close to it is causing any problems. He's just concentrating intensely on something..
I devise that's just a habit but I really instil you to talk to him instead of speculating this or that behind his vertebrae.
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