No offense, and I'll help you anyway, but isn't a science fair supposed to test your research ability as well as presentation ability? And I guess you can argue this is research, but you could probably find an article off google somewhere.
Anyway, FPS = Frames per Second. It's how fast your video card sends signals to your monitor with what it "sees." Usually it's split into 3 categories:
- Playable (60+ FPS)
- Semi-playable (25-60 FPS)
- Non-playable. (25 and below)
Granted, those numbers aren't set in stone at all and some people are able to play games at 25 FPS and below. It just all depends on how used they are to higher FPS gameplay.
Few things that are detrimental to FPS:
- Resolution
- Anti-Aliasing / Anisotropic Filtering
- Vertical Sync
- Hardware limitations (covers a BROAD spectrum)
- Software effects (also covers a broad spectrum)
With resolution, the smaller it is, the less of a signal the video card has to send, the faster the signal goes. Simple enough. Basically under any video card (no matter how powerful it is), you'll see some type of decrease in FPS when your resolution is raised. That's why, in benchmarks, most people benchmark different resolutions to give the viewer a better idea as to what one should be seeing performance-wise.
Anti-Aliasing and Anisotropic Filtering both play key roles in FPS. In short, Anti-Aliasing (henceforth known as AA) decreases the jagginess around objects and Anisotropic Filtering (AF) is responsible for making textures crisper when seen from afar. AA can be set from 0x to 8x and AF can be set from 0x to 16x. Obviously if you have AA and AF enabled, the video card must process more information, thus decreasing FPS. Rule of thumb is whenever the video card has to work harder, the lower your FPS will be. You can usually set AA and AF in the newer games (HL2 / Doom3) by going into graphics options, but in other, older games, they need to be set through driver profiling.
Vertical Sync is sometimes good and sometimes bad. What it does (or tries to do) is sync your FPS with the refresh rate of your monitor giving you less "tearing" effects in certain taxing applications. Say the refresh rate of your monitor is 75Hz: Your video card, if V-Sync is enabled, will be forced to produce <= 75 FPS, even if you could go much higher. Now obviously, your FPS will decrease in this situation if it's a game with which you get higher FPS than your refresh rate. During benchmarking you should always take off V-Sync.
Hardware limitations is rather obvious. To sum it up, if your hardware can't keep up with the demand of a certain application, then your FPS won't be able to keep up either. Many things can be responsible for hardware "bottlenecks": Video card, CPU, RAM, Hard Drive... pretty much anything in your computer if replaced with something better will yield higher FPS.
Software effects encompasses any effect or situation in a game that causes the video card to work harder. Things like rain, or heavy textured rooms; anything that makes the video card need to process a lot of information. Some of these can be turned off (i.e. rain in CS:S) to yield higher FPS.
To test the performance of your video card, I would first set an hour or so aside and dedicate it to benchmarking. Use HL2, Doom3, and
3dmark05 in your benchmarks. Test the main 3 resolutions that people would use... 800x600, 1024x728, and 1280x1024, pumping up the AA / AF each time you go through. For the Doom3 and HL2 benchies, use the timedemo tool (look it up) included to test. For 3dmark05, it's going to give you a score once you run it... and the score is sort of a universal benchmarking score, so include that. What's important is that you leave the rest of your system and settings constant; changing only the res. and the AA / AF.
Good luck, and hope you do well!
(If you feel like being nice, you could cite me as a source... PM me for info).