40 Worksheet Big Discovery LIFE Workbook with Puzzle Keys. Goes with the Discovery Channel documentary series Life. 4 worksheets (crossword, fill in, mix and match, and word search) for each Life episode: Challenges of Life, Plants, Creatures of the Deep (marine invertebrates), Insects, Fish, Reptiles and Amphibians, Birds, Mammals, Primates, and Hunters and Hunted (predators and prey). Applicable to science, life science, biology, ecology, environmental science, zoology, animals, botany, primat