I noticed a few weeks ago that my 15 year old son was with us eating at a restraunt and when he was eating he was shaking guite a bit like a old man putting food onto his fork to eat. This concerns me. I did noticed when he was younger he was getting his ears or eyes tested and he had to hold his head still and you could tell some shakiness in his body.
Hello, I recommend he be evaluated by his pediatrician for the following metabolic profiles if not already done: THYROID FUNCTION (using FT4 and TSH), LIVER ENZYMES and INR to establish liver integrity, COPPER LEVELS in 24 hr. urine.  His pediatrician could also order an MRI of the brain (without contrast to start) which can be repeated WITH contrast if something suspicious surfaces on the first one.  If any of the metabolic profiles come back POSITIVE for something out of balance then, it should be corrected (with a consultation to appropriate specialist if necessary).  If the profiles are NEGATIVE for metabolic abnormalities and the imaging studies are negative for architectural problems then, a referral to a PEDIATRIC NEUROLOGIST would be in order.  The most COMMON pediatric movement disorder consistent with your description is ESSENTIAL TREMOR which is usually successfully controlled with medication.  Hope I have answered your query. Let me know if I can assist you further. Take care Chat Doctor. 