This is a great book for girls or boys. My kids ages 6 & 8 think it is so funny, and it will last for several years as some of the math is within their reach and some is a bit too challenging. However, even the 'challenging' parts are lots of fun to read, and funny to watch the character going through her day. The artwork is beautiful and creative - very original. Please note, though, some of the pages refer to calculating 'quarts in a gallon' or 'feet in a yard', which isn't relative to Canadian kids using the metric system. There are references to the metric system too.
So if it was all metric I would've given it a 5!