I said second arc, but I guess it would really be more like a third arc. Here are my ideas for that as they stand now, but they will, of course, fluctuate based on how the story unfolds. We are all co-writers here, after all XD. 

Arc I: We get shrunk down and have to survive the backyard, and then decide which side we're each on when it comes time to destroy or defend the Crystal Battery.

Arc II: We leave the yard and live among the faeries while trying to find a way to return to our normal sizes, including some adventures around the world to different spots of magical potency. At the end, we're able to somehow return ourselves and all the other survivors found to normal size, but we retain our faerie powers and have the ability to change back and forth between Human Size and Faerie Size at will. 

Arc III: All the survivors from the various faerie experiments are given the option of joining the private school, which as far as the media is concerned is just a normal learning center set up for survivors of the kidnappings. The fact that they were shrunk down or developed faerie powers is, of course, a closely guarded secret, though perhaps government agents could come sniffing around to help create conflict, we'll see XD.