I think there's a difference between "I tried to use PV = nRT to solve my homework and it didn't work!" and "How can I effectively demonstrate the ideal gas law at home?" For me, the difference is very clear - only one of these questions is interesting.
Having received an undergraduate physics education, I can answer questions on adiabatic expansion easily. I am not sure, though, how close the air in this room is to being an ideal gas. I'm not sure of a good way to build my own barometer or thermometer. I have a basic idea of what these things are and how they could be constructed, but I think it's likely I could learn a great deal if knowledgable people were to answer the question about this simple experiment.
I don't mean only that I would learn the sorts of things I'm supposed to learn in a shop class. I mean I would learn actual physics.
For example, there was one question a while back about how one can measure Avogadro's number at home. I already knew the answer about Brownian motion, but didn't know the one about creating a monolayer of oil on top of a body of water. That answer was physically interesting to me because it led me to wonder why the oil would 1)spread out to a single layer and 2)stay contiguous once it had become a single layer.
The process of thinking about, devising, and executing such simple home experiments is likely to be engaging and educational, even on the level of people who do have significant physics education, and is not equivalent to entry-level theoretical questions.
Also, for people who, unlike I, are already very skilled at experiment, I can guess it would be an interesting challenge to discover simple home experiments that demonstrate physical effects people are interested in observing.