Welcome to Science Buddies!
I see that Keith has helpfully provided you will a link to the project ideas on this website. We have lots of ideas for zoology science fair projects. Here is a link to the list of the zoolofy projects:http://www.sciencebuddies.org/science-f ... logy.shtml
Why don’t you look through the list until you find something that looks interesting? Then, be sure to read through the procedure to make sure you can do the experiment. Also you should read the bibliography and search for more information from scientific sources to learn as much about the topic as possible. This process should help you develop a unique question that you can answer with a carefully controlled experiment.
I have some precautions about selecting a project. If you select a project using vertebrate animals, you will need to check with your local scientific review committee to get approval to proceed with the project. Ask you teacher more about this, if necessary.
Also, if you select an insect project, make sure you can provide an environment that is at least 65 degrees Fahrenheit until the experiment is completed. Every winter I judge insect projects with no results, and these projects do not do as well at the Science Fair as projects that do have results. Projects with Daphnia or earthworms, for example, are easier to do in cooler weather so these projects are usually more successful.
What projects have you been considering? What are you interested in doing for a science project?