I've been teaching high school and/or college for close to 15 years now, and anecdotally I haven't really seen the needle move one way or the other (at least in that dimension). The one trend that I've maybe noticed is that the students who are more politically engaged tend to be somewhat more radical in either direction--either very right wing or full-on commies. Even that doesn't seem like an especially pronounced effect to me, though.

I think it's more common to see a disengagement from politics, at least for issues that don't affect them directly. That's reactionary in effect since the status quo is reactionary, but the motivation (generally) isn't reactionary. What I see more than anything else is a pervasive kind of despair, whether that manifests as gallows humor, cynicism, ironic detachment, or nihilism. Some kids manage to forge that despair into righteous anger, and some of those manage to point that anger at the right target. Most of them, though, are just pretty checked out. That ends up reproducing the behavioral politics (if not the motivation) of libs.