"white middle-class values,
In other words, they want kids taught WITHOUT values. Any so called values, which do not contain morality, are no values at all.
It does seem like the schools are refusing to teach middle class values or the history of the USA or the Constitution. Middle class values means you work hard for what you expect to have --- you won't have everything, but you'll have enough to live on and a little left over --- what's so wrong with that? Upper class values are fine if you inherit money, lower class values mean a life of welfare handouts.