Elizabeth George Speare is a Newbery Award winning author. This book 'The Bronze Bow' is set in the time of Christ and is a good read, especially at Easter. This book would be for the Older Elementary and Junior High and up. I enjoy reading it still. She has written several other children's books that are worthwhile as well.
Armstrong Sperry creates a wonderful story and many of his books introduce other cultures or are historical fiction (old west and sailing novels) . Some of the books are for elementary readers, and others are for junior high, more because of the length of the books and vocabulary than because of any other reason. Many of his novels are on tape, and we have enjoyed getting them at the local library; they are great for car trips.
'Misty of Chincoteague' is Marguerite Henry's best known book. A movie was made of it back in the fifties. There are several sequels to it as well. Marguerite Henry is famous for her horse stories. Most of the books are illustrated by Wesley Dennis. She is an excellent author who is historically accurate in her writings and does an excellent job creating her characters. I have enjoyed reading many of her books to the children.
Mrs. Henry does write about a number of other animals. 'Brighty of the Grand Canyon' is a story about a mule out in the Grand Canyon who works with an old miner. After you have read the story, you can watch the movie. Marguerite Henry also wrote and illustrated a book about birds. She has even done a few picture books. One I have is 'Five O'clock Charlie'. The books are written for a middle elementary reader. A little bit beyond chapter books. As with all well written children's books, they are enjoyable by all ages.
If you haven't read these, they are good ones to add to your library list.