Ballet Shoes, by Noel Streatfeild, was one of my favorite books when I was about ten or eleven. I'm pretty sure I went through the "shoes" series in short order. Ballet Shoes, Dancing Shoes, Theatre Shoes, and Party Shoes--those titles are the ones I believe makes up the quartet, though characters change a bit from book to book.
Now, just in time for dance-crazy, seven-year-old E. to enjoy before she begins her first dance classes, is what appears to be a promising adaptation of the book for film. The movie stars Emma Watson (Hermione from the Harry Potter flicks), and here is a link for the preview of the movie. It opens in the U.S. on Tuesday.