In the 1800s, the Underground Railroad was a system of secret routes and safe places to hide for black slaves trying to escape to freedom. This astonishing book details the evidence that led up to the acceptance of slavery as well as the rejection of it. Readers will discover that when faced with evidence of the plight of slaves, such as slave auction posters, engravings, photographs, and interviews, white people had varying views depending on whether they benefited from slavery themselves. Readers will learn how prejudice and circumstances at the time of an event can influence people's interpretation of evidence and how that perspective can change over time. They will also learn how to use critical thinking in their own examinations of evidence. Present-day examples show how history repeats itself when evidence is denied or interpreted to one side's benefit. Teacher's guide available.