यह Publication Issue अपनी भाषा में मौजूद नहीं है, में देखें: English (en),
या गूगल अनुवाद का उपयोग:  
हिन्दी भाषा (hi) | भाषा बदलें (Change Language)

Students will demonstrate their understanding of ways to improve and conserve soil as they email an ECHO intern in Africa, respond to a quote from the 19th century warning of civilizations’ impact on soil, and investigate the “Dust Bowl” soil disaster in U.S. history.