Middle grade children's novel.

What happens when three children spend the day in the supervised daycare program of a FL resort motel, but at the end of the day, their parents don't come to pick them up? The motel manager and the uncaring-caregiver want to "do something with them," and the children fear the worst. So the next morning, they just leave the motel and start walking home. Home is six hundred miles away, which leads to an enthralling story of their trip, the people they meet, the ways they find food, frightening experiences, and their worry about what has happened to their parents. The children change and mature during their journey.