Hello, Nicole!
I was in your position as a former tenth grader. The way I found a science fair project was by 1) listing areas I really like and 2) researching, researching, researching for topics! I didn't even know about Science Buddies as a tenth grader, so use this valuable resource to your advantage! It's really nifty!
Since the expert with the post above mine pretty much covered researching, I'll talk about step 1. It's more important than it sounds. Listing topics you like can help you identify what you'd feel excited to work on, and would also make the science fair experience all the more enjoyable. Listing also helps you become more organized, which is an important skill. After creating lists, you can scan through what you wrote and circle
your top three to five choices. Then make those choices more detailed. Chances are, all choices would be equally great ideas for a project!
Need an idea or some inspiration?
http://www.sciencebuddies.org/science-fair-projects/project_ideas.shtml
Want to read up on awesome projects and science/math-related news?
http://www.sciencebuddies.org/blog/index.php
Enjoy!

-RM, Expert