What are some of the reasons that a healthy 3year old would continuously have a high fever
:)

Could be many things: ear infection, flu, right down to getting a molar.
Try some ibuprofen (Advil for Children). One of the regulars here, J9, would a good source of knowledge.

Thanks NK, you did a great job as usual. I just have a couple of questions to help pinpoint.

What is the temp?
How long has it been going on?
Do you notice any other changes?