When I was in 8th grade I did an experiment that found that mold grew better nearer a cathode ray tube computer monitor. I had, however, in retrospect, failed to control for the CRT monitor being a source of heat and light (if not much). I also did not verify it wasn't just due to the one side if the table being closer to something unrelated in my basement. I did very well in the science fair anyway (I have a plaque somewhere, and I think I had gotten it for the state-wide level), as for a "school experiment" the competition bar is quite low, and there are a ton of other factors on which you are being judged than "scientific accuracy". This kind of research is really no better than the people reporting homemade experiments constantly whom we often label "crackpots".