I went through the ScienceBuddies site with my 8yo son and the project that appealed to him was the one on scale that was not a full project.
Like many boys his age he loves models, science and math. He builds scale hobby cars, flix trix bikes, rockets etc. He has learned that models of airplanes/rockets and houses save money, are easier to make design changes, and save lives.
He has been busy learning about why scale is important and what it is. He has determined by sight, not measuring, that his 3 inch flix trix bike is too big to look realistic next to his 1:24 scale car then measured to see why: the scales were different.
He also made a model without regard to scale and one with regard to scale to see which one was more realistic. The original question was: How can I make my models look realistic?
HOWEVER, he doesn't love the fact that his models are not really science and I know what he means - he wants to make a model and test it... but what kind of model can an 8yo actually test so he can compare it to the full size object??
We have tried to come up with another question/hypothesis that he can build or test within the next few weeks but they are just not quite what he's looking for.
Some questions: Does it make a difference if my model is built to scale?
The answer was yes if the difference was "Does the model look realistic?", BUT he wants to TEST if there is a difference if the model is built to scale by making a model then making the object. What is realistic for a boy to make?Is it really easier to test a model than a full size object?Is a model as accurate as a full size object?
So, I'm really looking to guide him in building something to test but he is stuck because he is thinking rockets, airplanes and nuclear weapons (lol) and I'm not much help to him.