In ur cousins case, it seens like she is one of those students who might have studied in a good school but might not have put much effort into studying math ..thats probably why she has touble with math. Not everyone can get the ability to understand math easily..it may require some time. And as for reading Shakesphere in ninth grade, i dont think there is anything wrong with reading it. She might not understand it completely, but understanding the basics of the story is good enough at her age and she should be encouraged to read more. And dont discourage her inclination to read more…just because she didnt understand Harry Potter books. Even though HP books are written in quite simple language, Rowling uses a lot of her own vocabulary and also if she was starting to read the story frm the first edition…it takes a while to get a grasp of the story for a some people. Its mostly becasues the first few chapters of the books…were a little too descriptive….i am a big fan of HP and i love rowlings way of writing..but i know some people needs a while to get a grasp of it. In my opinion you should make her watch one of those HP movies first and then let her read the book..it will help out a lot!!

p.s. Shakespeare is condsidered highschool level reading. I read Romeo and Juliet in 9th grade and Macbeth Junior year.

And you should improve your own English skills, by learning how to write and type correctly.