While reading-to is valuable, and this is suitable starting at age 5, my own personal experience is even better. I read this because I was curious and saw it on a list of Best Books, when I was age 8 or so.
While being read to is great, reading it on your own is even better.
Because of finding some really great books at that age, I became a reader, and read a lot.
Because of all the reading, my grades in school changed from Bs and Cs to straight A by 6th grade, but that is NOT the whole story.
I continued reading a lot (and remember, Charlotte's Web was part of the sprark that started this), and aced my ACT scores (like SAT), with 99% in 3 of 4 categories. Sure, there were other factors, but looking back, reading a lot was by far the key factor.
So, if you have a 7 yr old or 8 yr old that is reading, and hasn't heard or read this, it is a great opportunity, boy or girl.