My take is that she reminds them of that sort of of irritating busybody mother that is always active in school stuff -- I'm sure you remember the type.
That ... plus kids today seem to have much better BS meters than we had when we were their age. They're a lot more cynical, even if naive. And they haven't really seen Palin do anything to set herself apart from the parody that Tina Fey created in 2008. It's still just folksy talk and catch-phrases.
BS.
The amount of obvious BS that kids today swallow whole without even realizing it stinks is appalling. The "global cooling" scare of the 1970s was laughed at. The current "global warming" scare is taken with foolishly earnest seriousness. In the 1970s, queers were viewed rightly with derision. Today, the oxymoronic idea of "homosexual marriage" is taken with foolishly earnest seriousness. Similar examples abound.
Ban DHMO!!!
The "kids" in 2008 voted overwhelmingly for Obama.
What an amazing "BS meter" they must have.