As a 10th grader in the US school system, you should have had some algebra and Earth Science courses by now. The problem with most of astronomy is that interesting questions often require expensive equipment ( telescopes), or some mathematics and physics background. But, lets suppose you can take advantage of the Internet and get a 'pen pal' located a 1000 miles away in another city. On the same night, and at EXACTLY the same time 'Universal Time', make a CAREFUL observation of where the Moon is located with respect to the background stars. You should be able to discern a slight (about 1/2 the Moon's diameter) shift in position due to parallax. Then, with a little geometry, you could estimate the distance of the Moon!
Here's another one. Plot the local rising and setting times ( Local Standard Time ) at your location announced by the local news station, or printed in the newspaper. Plot it for each day of the year using daily 'readings/announcements' or 'historical data from older copies of the paper in the library. Figure out why the pattern you see in the data occurs.
Determine the affect of light pollution in your area by using a star chart, a pair of binoculars, and noting the faintest star you can see from various locations in your town, and at various distances from it out into the countryside. What would you recommend to the City Council to improve your view of the sky? What is the most serious contributor to your local problem?
Do a study of whether the Full Moon is really correlated with more crime, more births, in your city by using reports in your local newspaper, or data at a local hospital or Police Department.
Does water really go down the drain in opposite directions in the north and south hemispheres? Use contacts on the Internet in Australia, and other southern or equatorial countries to set up a data base of 'toilet flushes'!