Ceiling height and room temperature
Our hypothesis has been proven to be true. The higher the ceiling, the lower the room temperature.
Houses with low ceiling are suitable for colder climates because they help to keep the house warm, whereas houses with higher ceilings are suitable for warmer climates because they provide better air ventilation and keep temperatures lower. However, rooms with higher ceiling will require more powerful air conditioning compared to the lower ceiling rooms, as the volume of air in the room will be greater.
What would happen if the science fair project were to be repeated using lamps of different wattage?
The science fair project can be also repeated by making the floor space of the box bigger or smaller.
Attic ventilation for homes - http://www.factsfacts.com/MyHomeRepair/ventilation.htm
Ceiling height and cooling cost - http://www.newton.dep.anl.gov/askasci/eng99/eng99420.htm
Basic safety requirements. Handle electricity and hot lightbulbs with care and proper protection/gloves.