My 6th grade technology class has just finished making hot air balloons out of tissue paper and launching them. We also wrote letters to Leon Gambetta helping him escape Paris in a hot air balloon after reading Horses with Wings by Dennis Haseley.
I then used this article from Wired for a lesson last week.I posed the question of whether the premise of the movie UP was possible? The class voted and then I told them that we were going to prove it one way or the other.
I then made them figure what questions to ask and what we needed to know to "prove" it. They had the Internet as their resource. It took most of the hour, but they figured it out. Learning to ask the right questions was an important part of this lesson that I emphasized to them. They had to figure how much the house weighed, how big the balloons are, how much lift helium has, and the volume in a balloon.
We then talked about the errors in our hypothesis such as neglecting the mass of the string. We also talked about other practical concerns mentioned in the article and in the comment feed such as the fact that houses are not designed to be lifted. Lastly we looked at the clusterballoon website of people who launch themselves. The students were fascinated by this site.
Overall it was a very good lesson and I plan to repeat it again next year with one change: bring in some real helium balloons and have students perform an experiment to discover the lift of helium by measuring the balloon's size and tie it to a weight on a triple beam balance.