Try B & N youth books
Plenty of youth books available at this book store and any employee on hand would love to point you in the right direction and will also provide recomindations.
There is a really good children's section. You can keep a precocious 8yr old interested.
I hate to answer with a question but what do they like to read and what is their reading level?? My son is 9 and is at the tail end of the Harry Potter series. Also there is the Geronimo Stilton series and there is a girl side to that series but I can't remember the name
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