My Josh, who is 8, is reading In Freedom's Cause - A Story of Wallace and Bruce. He is loving it. The book is pushing the limit of his reading ability, but I quiz him every now and then about what is happening to make sure he is comprehending what he is reading.
When I was growing up there was a series of books called Young Biographies. It tells the stories of famous people, but mostly through the childhoods. Maybe two chapters are given to their exploits.
I loved those books. I read them all Amelia Earhart was my favorite. I must have checked that one out a dozen times.
I have "The Cat of Bubastes" for when they start their Classical sequence with the "Ancients" in February.