Dandruff in kiddos.

So my daughter is almost 7, and being monitored by an endocrinologist because of her maturing/ growing too fast. She said her growing so quick, that it could cause the increase of skin cells to shed at a faster rate. Well, we didn't have any issues up until last week and it's like BAM dandruff out of no where. We have tried head and shoulders, coconut oil, baby oil, other oils that are supposed to help with moisturizing hair and scalp, swapping shampoos and nothing has helped so far. My main concern is her getting picked on at school for it/ kids thinking its lice and not understanding it's just dandruff.

Does anyone have any ideas on what else I can try to do to help her, I feel so bad because you can literally see it flaking off of her scalp.