Topic for Science Fair

Question

I'm in middle school and I need suggestions for a topic for our science fair 

Answer 1

You could test to see which batteries last the longest, testing them in flashlights, for example.  Or, you could test the effect of acid rain on plant growth, watering half of a group of small plants (bean seedlings work fine) with regular water, the other half with water which has had vinegar or lemon juice, both acidic, to it.  Or, you could see what effect the size of pieces of alka seltzer has on the speed of dissolving.  You would time how long it takes to dissolve whole pieces, quartered pieces, and crushed pieces of alka seltzer.  You'd have to make sure that the amount of water is exactly the same and that the temperature of the water is exactly the same, for all three sizes.  It is also a good idea to repeat the experiment at least 3 times to have good results.  Good luck.  I hope I helped!