I'm planning on opening a children's bookstore. I have a ton of marketing thoughts. Here are just a few:
(1) Children's books are generally sold at retail in the big box stores (except for a special sales - generally not the best quality books are sold cheaper). I am hoping to move more volume by offering 10% off all books, everyday to everyone.
(2) Teachers are goldmine. The average teacher spends $1000 out of pocket each year (I should know. I am one.

). I will offer 20% off to teachers, a teacher wish list (gift registry), referral programs, and special events (including literacy workshops).
(3) Lots of special events - storytime, book clubs, authors, summer camps (1/2 of my space is classroom space for workshops, tutorials, etc.), holiday events (like Storytime with Santa), character parties (Clifford, Arthur, Curious George, etc.), and more...
(3) Flyers, bookmarks, ads in local parenting/kids magazines and newspapers, etc.
(4) Build a relationship with the local university education department (I already know all of the key players), the local reading council (I'm Vice President), school district (my place of employment until I open), and libraries.
(5) Contribute / Involvement with the local Education Foundation, Chamber of Commerce, and other similar organizations.
(6) By invite ribbon cutting & reception night before opening, opening day events (well advertised - authors, magicians, clowns, storytellers, characters - big, exciting day), big grand opening plans, holiday plans, and more...
I believe advertising, marketing, and excellent customer service is key...