Fins

From Randy Wayne White, the New York Times bestselling author of the Doc Ford series for adults, comes Fins, a high-stakes, masterfully plotted story of courage, friendship...and sharks!
The world's shark population is in trouble for a sad, simple reason: shark fin soup. And although it's illegal, poachers have been targeting Florida's biannual migration of blacktip sharks.
Marine biologist Doc Ford needs some assistance protecting the sharks and enlists the help of three kids—Luke, Maribel and Sabina. Luke is brand-new to Florida from the Midwest; sisters Maribel and Sabina have only recently arrived from Cuba—and all three feel like fish out of water. It's going to take some convincing for them to work as a team and to recognize in themselves the courage, wisdom and tenacity that Doc sees in them.
Together they form Sharks, Inc. and are given an important assignment: to set out each day on their small fishing boat in hopes of tagging sharks for Doc's research—and to stay away—far away—from any possible poachers in the area.
The trio certainly isn't looking for trouble, but when they come face to face with danger, survival requires them to rely on each of their own unique gifts, and especially on one another.