Found this little gem in issue #64 of All Star Comics from 1977.
Seriously, the kid asks Superman if his father has the right to hit him, and Superman’s answer is basically “yes, so long as he doesn’t injure you.” So, Superman is okay with hitting kids. Of course, this was pre-New 52 Superman. Hell, this is pre-Crisis Superman. So, it’s possible that Superman currently does not condone violence against kids, but we’ve seen nothing to confirm this.
But man, Superman is a dick.