Times change, children grow up, old ways disappear, and new ways take their place. The story of RACHEL shows the passing of the years and the changes in the lives of the Collier family, the town they live in, and across the entire United States in the early 1900s. As Rachel becomes the new teacher in the Mercerville School, the quiet days that followed her going to college give way to the violence of World War I.

In this sequel to A Sign of the Times, the teaching of history through literature helps students re-live the years leading up to the First World War, when the weapons and war machines that were built showed the world the power and terror the Industrial Revolution had created. When Rachel gets marries and starts a family, she believes that her life is complete. Her husband is sent away to the Great War in Europe and her life, and the lives of millions on both sides of the Atlantic Ocean, becomes a test to see if she can survive in the new world alongside machines that could travel long distances in a short amount of time, communicate with people in other parts of the world, and even fly.