Book licensing fees

Could you answer a question for me. I am an author and a large organization would like to produce an event around my children's book - something like a Polar Express but not exactly. They would charge a fee to this event and give out the product I sell with my book to the children and sell the book in their stores. This would deb a money making event for them. Do I need to charge them a licensing fee for this use? I realize they will pay me for the books and products but do I charge them a licensing fee for the six weeks they will hold this event. They may be calling the event the title of the book. Thank you.