Kids are intrigued by examining how each kind of animal is adapted (it body is constructed in a way) such that it carries on life in a particular way. Most basic are adaptations for herbivorous (plant eating) versus carnivorous (meat eating) behaviors. (In the following, please post questions that arise.)
Mammals: Have kids contrast the body structure of herbivores and carnivores and discuss how each is adapted to feeding and living in the manner it does. Type into your browser: herbivores versus carnivores images
Birds: Most insightful is focusing on a bird’s beak, how that beak adapts the bird to feed in a particular way.
Type into your browser: beaks of birds with names
Also view: https://video.search.yahoo.com/yhs/search?fr=yhs-adk-adk_sbyhp&hsimp=yhs-adk_sbyhp&hspart=adk&p=beaks+of+birds+with+names+video#id=6&vid=34234a42d9ed377dee2df7f804849001&action=click
Insects: https://www.youtube.com/watch?v=D1Wv57c_qY0