Good posts here, I'll add that it's important kids are around working class folks as it becomes much harder to do lib shit when you know people, it's why chud evangelicals who know a gay person are much more likely to be supportive of gay rights. Make sure they attend public schools and do at least a sport to interact with as many diverse groups as possible. This why finding a church/organisation that is pro-LGBTQ is so important to me, it helps build that foundation that being gay and/or trans is not abnormal. Same idea with the working class--seeing their struggles first hand is formative

Edit: public schools, after school activities, religious groups,etc are all ways to make friends and contacts with the working class. Post-college, that becomes almost impossible unless you are super intentional about it