I am a CS researcher in a corporate lab and a homeschooling father. I'll speak to the subject without snarking about word processing.
For the younger crowd, I can highly recommend Computer Science Unplugged. It is a great introduction to the fundamentals of computer science - algorithmic basics, information coding and entropy, finite state automata, and a bunch of other good stuff. Interestingly, the entire course is done without a computer. It has exposition, exercises, and games that reinforce those fundamentals.
It's about 10 hours of coursework, it's free, and it's geared toward the 8-12 year old crowd. My 7-year old didn't have any troubles with it, and was always hungry for more. The novelty of teaching computer science without touching a computer is also compelling.
Now, if anyone can recommend some good coursework on introduction to programming and basic algorithms for the 8-10 set, I'd appreciate it. I haven't found any good educational materials for Scratch (it's all pretty ad-hoc and amateurish), and I think Alice is a bit much for sit-you-down-and-start-programming. Any personal experiences?