Wow, this has gotten to be a really long conversation, and I haven't followed it all. If I've learned nothing else in 8 years of teaching, it's that long discussions of educational philosophy make me sleepy. I am interested in creative and unusual ways to "hook" students' interest, though.
Umami-mommy, several pages back, you mentioned that your son likes Doctor Who. I was inspired, and I've come up with a series of global/social/cultural studies ideas based on the most recent season of the show. I don't know if they're all appropriate for 8 year-olds, but unschooled 8yos tend to be a little atypical. I would not recommend using all of them or treating them as a curriculum. They're just ideas that might help spark some interest. I won't be offended if it's useless, and I apologize if it's no longer relevant.
Cool fun fact to establish my Doctor Who street cred - Matt Smith is the clumsiest human being in the world. The DW producers are terrified that he's going to fall off the platform that surrounds the Tardis engine and kill himself. They've had the soles of his shoes ripped off and replaced with special, high-traction sneaker soles to keep him from slipping. It hasn't helped.
This last season:
The Eleventh Hour - The Doctor meets Amy Pond and tells her he will come back for her. He returns 11 years late. Interesting related questions: For years, no one believed Amy about the Doctor. She's been through four psychiatrists (she kept biting them). What happens to people who no one believes, even though they're right? What about people who are gone for a long time? How do their families keep the faith and wait?
What you could learn about: Cassandra, Odysseus, Noah, Romeo and Juliet, the entire cast of The Tempest, probably some other people in Shakespeare
How this relates to social studies: Understanding ancient cultures, the Renaissance
The Beast Below - The Doctor and Amy visit a future England in space and meet the Queen of England and the benevolent Starwhale who is carrying Britain on its back. Interesting questions: What is the role of royalty in the 21st century? How has it changed? What people or groups of people have acted like the Starwhale?
What you could learn about: Any monarch you wanted, or several. The idea of service and heroism. The Holocaust and the Righteous Among Nations (for example the Captain of the MS St Louis, who seriously considered running his ship aground off the coast of England so the Jewish refugee passengers on board would have to be given safe harbor), any situation in which people acted selflessly to help others.
Tie to social studies: Politics. Civic responsibility.
Victory of the Daleks: Churchill accidentally invites the Daleks to help defend England in WWII. Interesting questions: Daleks are scary. Was WWII scary enough to make a Dalek-British alliance look like a good idea? How did the British really fight the Nazis?
Time of Angels: River Song says that she's killed "a good man, and a hero to many." Who might that be? Which historical figures would qualify? Why? And, the soldiers are also priests. When else has that happened? And River does some crafty things to send the doctor a message. How would you send the Doctor a message?
What you could learn about: Take your pick of interesting historical figures. And the Jesuit order and Pope Julius the I-forget-which-number. Also geocaching, which involves orienteering and map-reading.
Flesh and Stone: Amy has a really bad day and a lot of people get sucked into a hole in time. Interesting questions - what would be the result of making one event never have happened? What event would you get rid of? What event would you want to protect?
What you would be learning about: Historical cause and effect relationships
The Vampires of Venice: There are aquatic vampires. In Venice. Interesting questions: What other times and places might be useful for alien vampires operating incognito? What times and places might be handy hiding spots for other creatures? You can stick with the Doctor Who theme and look at Daleks, Cyberman, Silurians, Sontorans, Autons, and Weeping Angels, or you could branch out and do werewolves, regular vampires, zombies, and people with super-powers.
What you would be learning about: geography
Amy's Choice: The Dream Lord messes with everyone's heads. This isn't my favorite episode to use, but there's a lot in it about demographics. What do normal communities (i.e., ones that haven't been infiltrated by parasitic aliens) look like, demographically? What factors (events and crises) make communities differ from the demographic norms? What's it like to live in a rural community with few services?
What you would be learning about: demographics
The Hungry Earth: Some curious geologists drill a really deep hole and accidentally disturb the SIlurians, who don't like them much. Interesting questions - what's actually down there? Study some geology. Also, how do people tend to treat newly discovered cultures? Imperialism.
Cold Blood: Lots of people are taken prisoner. Some of them die.
Interesting questions - How should prisoners be treated? Learn about human rights.
Vincent and the Doctor - The Doctor and Amy meet Vincent van Gogh. Was Vincent really like that? Did people really think his art was horrible? Learn some art history.
The Lodger - The Doctor poses as a normal human. He's not very convincing. What kinds of things do people do to blend in in unfamiliar places? Learn some cultural anthropology. Also there's an alien spaceship (I've been assured it will appear in future episodes) looking for people who want to escape. If you could go anywhere, where would you go?
The Big Bang/The Pandorica Opens - River poses as Cleopatra - who was she? What did she do? Did she have the power to boss the Roman Army around? What were the Romans actually doing in Britain? What do we know about Stonehenge? Who was Pandora?
AND THEN - Rory guards Amy for 2000 years. What dangers would he have had to look out for? PLUS - museums preserve stuff. How? How do they decide what to preserve? How could you prove that an artifact is genuine?