9th grade science fair projects need to be more advanced than middle school projects. They will also need to be structured in a more professional manner. While middle school students can get away with not fully completing each step in the scientific method, freshmen in high school will not be so lucky. So my advice is to know every step of the scientific method or engineering design process. These 2 links will lead you to the details of each process. Don’t mess around because you will not fool anyone. High school is the time to get serious about your work, if you haven’t already.
There are many topics that excellent for 9th grade science fair projects. One of most interesting and important topics is to code your own robot. The 5 Programmable Mechanical Coding Robot Kit | Teach STEM Education for Kids and the II BBC Micro:bit Robot Kit | STEM Educational Toys for Kids are excellent engineering science fair project kits.
Freshmen that are interested in entering a science fair can start their topic search by browsing through their science text book. This will be either an earth science textbook or a biology textbook, in most cases. If the student cannot find something that interests them in these books then they can go to the library to browse through science journals.
The key to finding a winning science fair project is to look for a topic that is unique, interesting and that has some practical application to modern life. Science New for Kids is a great place to find items are for topics for freshmen level science fair projects. However, in order to win a science fair the student will need to create an angle that makes the topic even more useful, practical or interesting.
Once a topic and an angle have been selected then the student will need to conduct their background research. This will often help the student to refine their topic and angle and it will help them to define their project’s hypothesis. Finally, this research step will help the student to get ideas about how to set up their experiment.