My Teacher is a Diamond Thief! — Pamela Butchart

When Izzy and friends get a new teacher, they are immediately suspicious. Why does she have two computers set up on her desk? Why does she speak Spanish when they're supposed to be doing maths? Why does she have a pink wig and sunglasses in her car? And WHY DOES SHE HAVE A DRAWER FULL OF DIAMONDS? Because she's an international jewel thief, of course, and MUST BE STOPPED!