She is really smart in math, but I find her Math books a bit fluffy. They are full of anectodes and cutesy advice but doesn't really give much in way of math instruction.
The books themselves are very approachable, but the cutesy stories and examples aren't really that great. For the PP who thought they would purchase for their son, DONT! It is very girl based down to swirly cute scripty font and little sidebars that say stuff like Dear Danica-- OMG! MY Bff loves my current bfriend. How can i stop the hatin'? (yes, it was written in text language)
I thought about buying it for my daughter but I just couldn't get past all the superfulous crap. The math knowledge that is there is good--but it is hard to find and get into.
The bio on the back said she has a BS in two math subjects, not a MA, MS or ED or Phd.