This worksheet provides an image of a chicken focused on the digestive system as part of an overall unit on comparative anatomy. Students label the major organs of the system which are similar to the human and frog.
The chicken does have some digestive system adaptations , such as a crop, proventriculus, and gizzard, which is the equivalent of the stomach in other animals.
For a comparative anatomy unit, digestive systems vary based on diet. Birds are also adapted for flight, so they do not have teeth, but use the gizzard to grind food.
Students can also examine the bones of birds or full skeletons to see how avian skeletons are adapted for flight and compare that to a human skeleton. This coloring worksheet on humans and bird skeletons can provide a way for students to learn the names of bones and compare species. I have also collected turkey sternums over the years so students can see how the bird skeleton has a keel shape in order to provide stability during flight.