Who gives the insulin? If it's a nurse, and it's prebolused then maybe they need to talk more about what looks good and how hungry your son if feeling that day. Some kids go to the nurse, bolus for 1/2, eat, come back with all the leftovers and they see if any additional insulin is needed.
Eight is sort of a tough age - not quite mature enough to say, " I'll eat this but not that" ahead of time but there may be oher things going on other than just appetite. Maybe there's a game or some other social thing that he's rushing to get to? Is recess tied to lunch? Could he be sharing his lunch? Maybe parts of his lunch are no longer "cool" or some kid mentioned that only weirdos eat bananas
Mom to DD now 17, dx @4
G4 @ 15
"Happy Birthday, Dr. Banting! Now... let's eat cake! Because of you, we CAN!" - MCS