The Falling Action starts when the bombing raid is over. Also when Ms. Smith comes to get Jamie and Ada. Its the Falling action because its the end of all the chaos. Also because it leads into the Resolution.
One of the symbols of the book was Butter. Butter is Ms. Smith's horse. She symbols Ada's Happiness because Butter was one of the things that made Ada Happy. The foot can also be considered a symbol. It would symbolize Ada's Saddness because that's what causes it.
The Resolution of the Story is when Ada and Ms. Smith get back home. It's the resolution because they are reunited. Also because its the end of the book. It also leaves us without knowing what happened to Mam