Thanks Eridrus for this. Your clustering approach looks promising. I've been chipping away at this with a more straightforward heuristic based on parts of spee

Thanks Eridrus for this. Your clustering approach looks promising. I've been chipping away at this with a more straightforward heuristic based on parts of speech, just examining a hundred questions at a time. It turns out that filtering things down to the Direct Object and Noun-Subject (as identified by Google's NLP) filters out a lot of the noise. And then, the vocabulary of children under 10 years old is a finite enough that with a short blacklist, I'm getting quite a good hit rate for the first few hundred questions I've gone through. With a little more testing and refinement, I think this might get me what I want but I'm going to dig into sentence clustering if I hit a dead end. In case you're curious, here's the last few questions I processed as an example: How is an eraser made? > Topics: eraser Why do rainbows always have the same colors? > rainbow, color How do electromagnets work in devices like loudspeakers and microphones? > Topics: electromagnet, device, loudspeaker, microphone What is frostbite and why does it make your skin turn black? > Topics: frostbite, skin How can you see yourself in a mirror? > Topics: seeing, mirror