@angelo: in any case, I wasn't suggesting solving calculus problems at the time of posting, but when registering, so only once in a user's lifetime.
]]>I can imagine at least two disadvatanges to such a system, but I prefer other eyes consider this and wish to hear other points of view.
Gerhard "Ask Me About System Design" Paseman, 2011.08.10
]]>At the moment I count only two closed questions on the front page; by historical standards that's actually really good. It might be useful to have a discussion again about people's impressions of the level of inappropriate questions, and what, if anything we should be doing about it. It is possible to deal more robustly with off-topic questions --- e.g. users can flag for moderator attention, suggesting immediate closure or deletion, and this might slightly speed up their disappearance. That said, closures these days usually don't involve the moderators at all.
]]>I looked at some of the captchas, five or so, they were all high-school level or at best basic calculus; question below this level are IMO rare.
In any case, I do not think this would work well. (Even if the site could have it at no effort for anybody, I'd be against it.)
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