Partly I get society and government helping kids. It is to our communal benefit to ensure all children have a basic education and to minimize poverty. One could argue it would be to our benefit to provide an advanced education as well. Without reproduction we would, of course, die out, so on some level it is also necessary that we have kids as a society. But I believe there should be no incentive or benefit of being married or having a family beyond the benefits of association (insurance, inheritance, etc.). There should be no tax credits or other monetary benefits simply for choosing to have kids. There should be no marriage benefit on your taxes for being married. I think these are discriminatory practices that simply would not be allowed in other facets of public life.
Funny, if you are married or have kids you get tax benefits singles and childless don't, yet I cannot have a business that excludes people based on their marital or family status. I cannot make hiring decisions based on that either as a business owner/manager. That is protected by law and I would get sued and fined. But the government sure can discriminate based on that status. It is ridiculous.
I do fully support education for kids and taxes going to that. I think more higher education should be paid for. All kids should be able to go to some sort of college, especially if they want to but cant afford to.