William Hudson 
The Mystery of Long Pine Key [EPUB ebook] 

Tommy has a hard time making friends. All of his schoolmates think he’s a weirdo. And his best friend in the whole world just moved away at the beginning of the school year. And to make matters worse, it’s Spring Break in Homestead, Florida. Instead of going on a family camping trip to the mountains of North Carolina, twelve-year-old Tommy Higgins will have to spend the week at work with his Marine Biologist Mom and Park Ranger Dad in Everglades National Park. 

As much as Tommy loves the park, he is not looking forward to a week of chores at the Long Pine Key campground. However, Tommy has a change of heart when he meets some new friends who are staying at the campground. But when things start to look up, items go missing around the campground, and Tommy and his friends soon find themselves on the trail of the thief, the target of a group of campground bullies known as The Rough Bunch.