"Trick or ...What?"

I somewhat cringe when we are out this time of year and random people ask my children if they are ready and excited for Halloween. These "well-meaning" people are really just making conversation- but my kids give them blank stares, and don't even really know what "Halloween" means or why someone would want to go to a stranger's door and demand "trick or treat". They do know that this Wednesday is the annual "Fall Festival" at church, and that it is going to be an exciting event! They have been invited to dress in costumes...
We have come up with some creative costume renditions from a book we have been reading as a family. I'm thinking of it as an "extension" of our literature lesson. Call it a "book report". The kids love their costumes- they have been wearing them for three days. I can't wait to post a picture. Until then, I will keep you in suspense... :)