From CK-12, U.S. History Sourcebook - Advanced covers U.S. history from Colonial America through World War I. This book provides high school U.S. History teachers and students with sets of primary and secondary sources about important topics. Some teachers will use it as a supplement to a traditional textbook. For those looking to leave the textbook behind entirely, it will provide a course with basic structure and continuity, and will reduce the burden of finding new primary sources for each class meeting. However, it is not yet comprehensive enough to meet the coverage requirements of, for example, an Advanced Placement test.

From CK-12, U.S. History Sourcebook - Basic covers U.S. history from Colonial America through World War I. This book provides high school U.S. History teachers and students with sets of primary and secondary sources about important topics. Some teachers will use it as a supplement to a traditional textbook. For those looking to leave the textbook behind entirely, it will provide a course with basic structure and continuity, and will reduce the burden of finding new primary sources for each class meeting. However, it is not yet comprehensive enough to meet the coverage requirements of, for example, an Advanced Placement test.

Understanding Biodiversity presents an overview of biodiversity, its importance and relevance to humans, all living things, and the Earth. It includes species pages and a template to engage and involve students in real-life data collection.