TV Line says that the actress, who previously played Suzanne Farrell in Mad Men, wrote the project.
Spencer revealed that the show is called Teach and described it as "Grey's Anatomy with high school teachers".
Spencer also starred in Hawthorne and has had guest roles in programmes including Castle, Private Practice, Bones and How I Met Your Mother. She also recently shot a part in the upcoming movie Cowboys & Aliens.
ABC Family is currently developing a number of new pilots including a project starring Raven Symone and a show about separated identical twins.