Examine the illustrations and see if are clearly drawn or if the images/photos are very clear. You will be easily reminded of this photo in your mind once you see the actual insect. A good example is "Field Guides for Insects" as well as "First Guides for Children" by the National Audubon Society.
Browse through all the details and information. Try to see how the classifications are done, if you could understand it well or if it is only making you more confused. In addition, decide whether the book can answer all the questions that you have when it comes to insects.
Many children show interest in insects also, especially since they are the playful stage. They love to explore the outdoors. A simple and easy to understand reference material will be good for them.
Small field guides are usually the handiest for they only measure 4 inches up to 6 inches. Moreover, small field guides fit perfectly in pockets and backpacks. Some are hardbound. This is more expensive but is more durable.