On the trail of the t. rex by Rex Stone

Jamie and Tess are members of Dinosaur Club – a network of kids around the world who share dinosaur knowledge, help identify fossils, and talk about all things prehistoric. One day, while exploring their home of Ammonite Bay, Jamie and Tess discover a secret cave with fossils all over the walls. They go through a tunnel at the back and discover some dinosaur footprints. When they walk along them, the two friends find themselves back in the time of the dinosaurs! It’s amazing, but dangerous, too – they’ll definitely need help from Dinosaur Club.