In this context, researching means finding out as much existing information on your topic/question as possible. This ensures that, not only will you be able to understand your topic well, but that you will be able to develop a question that will work for you. The more you understand at the end of this stage, the easier everything from here on will be.
Tips: Write down everything you already know about your topic in your notebook. Next to this list, write down all the questions you have and all the things you want to learn from the project. An important part of this list is “what you know that you don't know.” These lists will help you get started on your research, as the whole idea here is to find a series of bridges that take you from the first list to the second. Often, a number of bridges will be required – you will need to read books, talk to your teachers, search the Internet, contact scientists or other professionals involved in your topic, maybe read some technical or scientific journals and conduct an experiment.
For a science fair project, having an experiment is a critical part of the process. If you find yourself getting all the way there without an experiment, then you need to set your sights a little higher and add to your “want to know” list.
You should section off several (or many) pages of your notebook to organize all the information you gather. Remember to write down names, sources, pages, titles, website addresses and a summary of each chapter or article you read. Check with your teacher on the exact bibliography rules for your project.