Tom and Jamie can't believe their luck when they find a secret entrance to a prehistoric world filled with dinosaurs. Loaded with snorkeling gear, the boys decide to explore the cove itself. But there are some not-so-friendly creatures lurking, including a hungry plesiosaur that wants a snack. Interest Level: K-3 Reading Level: 4.0 ATOS Book Level: 4.2 AR Interest Level: LG AR Points: 1 AR Quiz: 134526EN Reading Counts Level: 4.2 Reading Counts Points: 4 Lexile Measure: 680.