Does anyone know if Wal-Mart will let me put up a flyer in their store about my work?

I'm a 14-year-old babysitter, dogsitter, and housekeeper looking for some extra cash for the summer. I would put up a flyer in my local grocery store, but the bulletin board is out of sight. So, I was wondering if anyone knew if I could put a flyer up in Wal-Mart.