I did some prep work on this during the summer, so we're ready to go with Le Voyage de Monsieur Perrichon. This is a 19th-century play that lends itself really well to breaking down into small "French bites." In keeping with some of Charlotte Mason's ideas about teaching language, I'm planning on reading short sections out loud, encouraging narration wherever possible, and emphasizing a few--only a few--key phrases from each lesson.
I also made up a set of paper people to go with the story. We used to use characters like this for Our Island Story, and all the girls really remember them even years later. I didn't draw them myself--I just looked for images of 1860-ish people online, pulled them into a Word file, and squished and pulled them so they were all about the same size (so that we didn't have a giant lady with a tiny man).