When Mrs. McGrady is diagnosed with cancer, Arthur and his friends all act differently to the news - Arthur and D.W. rush to her side with heaps of chicken soup and stuffed animals, Muffy tries to pretend that nothing in her life has changed, and Francine is so upset she can't even bring herself to visit Mrs. MacGrady. In this two-part episode, parents and kids learn how they can come together to support Mrs. MacGrady and each other - and Lance Armstrong makes a special appearance to show Francine and the Elwood City residents how they can take a stand, or ride a bike, for cancer survivors.