What secrets lie beneath the mysterious Shell Mountain? In this second book of the acclaimed "STEAMTeam 5" series, Sandia, Treeka, Evelyn, Ariana, and Mattie embark on a top-secret mission to unravel the mysteries surrounding Shell Mountain. Along the way, they uncover hidden treasures from the distant past and risk being discovered by the watchful eye of an ancient secret society! (Full Color Version; For ages 7+) This 8"x10" book has over 150 pages and includes over 40 illustrations and a glossary of STEM/STEAM terms.