The Young Explorers Club: Root Word Expedition is designed to help students decode and synthesize meanings for multisyllabic words by focusing on specific Greek roots such as 'bio', 'geo', 'phon', and 'graph'. The mission involves recalling the meanings of these roots, applying them to create definitions for words like 'Biology' and 'Phonograph', and engaging in creative exercises where students invent new tools by combining roots from a provided word bank. This resource emphasizes an interactive learning process that combines vocabulary development with creative thinking, aimed at enhancing students' understanding of language and its components.