Trains are naturally interesting. There is not a child out there that does not stop and look when a train goes by. They are big, powerful and demand attention. There is no other vehicle on the planet that hauls that many different freight cars and passenger cars as a train does. A child can engage in the coloring book, especially if they know about trains and love them. If not the person around the child while they color can explain all about them. Hearing about them while they color them will teach them about trains.