What are some science fair projects on plants that contain a VARIABLE and a CONTROL?

I did this in my botany lab: I had two bottles that rolls of camera (picture) film usually go into. I put some dirt, fertilizer, more dirt, and then 8 plant seeds.





Then, I placed them camera rolls (that has the dirt, fertilizer, and seeds in it) in a dish that contained a miniscule amount of water, but just enough water so it could help my plants burgeon. OK...so, I had 2 of these plants EXACTLY like this. I placed them both under a lightbulb 24/7 for two weeks.





However...I made one of the plants my VARIABLE by putting a styrofoam cup over the camera roll (that contains the plant inside it).


And I left the other plant alone...which was used as my CONTROL.





I did this study to show the effects of a plant not having an abundant amount of light. Thus, the plant (my VARIABLE) still grew, but it wasn't as green as the CONTROL plant, and the VARIABLE also died after the first week...it started withering over. My CONTROL plant was growing just fine, and it burgeoned very rich, green cotyldeons. Basically...my experiment showed that without an abundant amount of LIGHT, a plant will eventually die off.


By the way...I got an A on this....(and this was in my college botany class). Just make sure that you remember to add enough water in the dish so your plants still have the chance to grow. :)


Good luck! What are some science fair projects on plants that contain a VARIABLE and a CONTROL?
Well, if you have long enough to grow a plant, I would suggest effects of fertilizers. Your control could be using the nursery's typical fertilizer while the variables could be various other fertilizers (ie- worm, horse, cow, chicken)

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