Originally Posted by Jodie
the gap between her knowledge and her schoolwork will grow even larger
It is my understanding that this is a frequently-used comment by schools to encourage parents to allow children to slip into underachievement. It is also my understanding that lack of mental stimulation changes the brain and makes it more difficult to pick up the pace and learn later.

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what happens then? I have no idea what to do... I feel so unprepared for this.
You may wish to study about advocacy. Other posts point to many helpful resources. A good first step is often having your child evaluated (IQ tests and achievement tests), providing a basic set of facts to work with. If you are in the United States and your child is profoundly gifted (99.9th percentile), the Davidson Young Scholars (DYS) program may be of interest.