torekp:
The extent to which you can control the peer groups your kids socialize with is quite large.
Yes, but you have only so many possible peer groups to choose from; it's not like you can custom-design one. Ultimately, your kids will internalize the norms and taboos dictated by their peer group, and your attempts to question them will make you look stupid and obnoxious in the kids' eyes. Until of course they grow up (which happens extremely late in our society by all historical standards).
Some religious sects, for example, control that socialization very tightly. The wisdom of such an approach is debatable, but it's definitely possible.
Most people do it, not just religious sects. One of the main things (if not the main thing) that motivates people to work hard is to be able to afford to raise their families in places where their kids' peer groups will inculcate respectable middle-class values and attitudes. Religious sects are different only in that they want to eliminate some influences that pervade the mainstream culture (including the youth culture) today, and which are considered more or less OK by most other people. Typical middle-class people are instinctively horrified by the though of their kids being exposed to a peer group that espouses underclass norms, just like members of religious sects are horrified by the prospect of their kids being exposed to norms hostile to their sect. In both cases, the fears are absolutely justified if you share their respective assumptions on what the kids should turn out like.
As for the amount of attention poured into the control and oversight of kids' activities and peer groups, I'm not at all sure that modern helicopter parenting, which has become the de facto standard for middle classes, is any less intensive in this regard than the parenting practiced by members of strict religious sects.
A hybrid approach might be to influence (rather than strictly control) the peer-selection process and also attempt to immunize your kids to the worst aspects of their peer culture.
Sadly, this is often the equivalent of tilting at windmills. The kids' blind conformity and fanatical adherence to their peer group norms, and their fervor to ruthlessly punish and ostracize their peers who fail to live up to them or who end up assigned low status according to them, is rarely matched by even the most fanatical and close-minded adults. This problem is exacerbated today by the fact that in the contemporary culture, the adulthood is delayed far past the ages at which kids were expected to join the world of adult society and adult norms in the past.
Sadly, this is often the equivalent of tilting at windmills. The kids' blind conformity and fanatical adherence to their peer group norms, and their fervor to ruthlessly punish and ostracize their peers who fail to live up to them or who end up assigned low status according to them, is rarely matched by even the most fanatical and close-minded adults.
As Bongo said, "teach them to hide it". That is, let them know that they can outwardly go along with peer group standards while inwardly reserving judgment, or holding a different judgment. Also...
A while back I did a couple of posts on the care and feeding of young rationalists. Though it is not new, I recently found a truly excellent post on this topic, in Dale Mcgowan's blog, The Meming of Life. The post details a survey carried out on ordinary citizens of Hitler's Germany, searching for correlations between style of upbringing, and adult moral decisions.