The At Issue series includes a wide range of opinion on a single controversial issue. Each volume includes both primary and secondary sources from a variety of perspectives -- eyewitnesses, scientific journals, government officials and many others. Extensive bibliographies and annotated lists of relevant organizations to contact offer a gateway to further research.
Kallen has written more than 350 nonfiction books for children and young adults. His books have covered a wide arc of human history, culture, and science. Kallen is also an accomplished singer-songwriter and guitarist in San Diego, California