Phredde and the Leopard-skin Librarian

What do you do when your school librarian starts dressing in leopard-skin and goes off chasing dinosaurs? A school excursion to the Big Koala goes horribly wrong when Phredde, Pru and Bruce - and their vampire teacher Mrs Olsen, and Miss Richards, librarian and martial arts expert - head back into the time of the dinosaurs, not to mention giant marsupial lions, a dinosaur with diarrhoea and an exploding volcano. Who will save them? Can one kid, two phaeries, a vampire and a librarian dressed in leopard-skin survive in the past with just a laptop computer, a flying carpet and a plastic spoon? Ages 7-12