I don't own the pathfinder beginner box, but I got hold of a similar product when I was even younger.
I was so fascinated by it, that I looked up all the words I didn't know in the dictionary (which was a really slow process back than).
Also it started me reading every fantasy book I could get my hands on, and I soon moved on to other genres as well.
Gaming is a great way to get in contact with a language in my opinion. Learning to read and speak a language and enjoying yourself in the process sounds like a good idea to me.