What is the theme of gone by Michael grant?

The reoccurring theme of this book is quite cliche, but it is teamwork. Suddenly thousands of kids roam freely around the perimeter of Perdido Beach. What causes them to withstand obstacles only Science Fiction can create? Teamwork. Who strives to bring back technology? Computer Jack. Everyone is held together by who? Sam. Who runs the daycare? Mary. You get the message. :-))