Editorial: First-time voters must be left alone to make their choice. Even by their teachers.

When it sees today’s high school seniors, the union representing Chicago Public Schools teachers doesn’t just see young minds needing nurturing; it sees voters for its pet causes.

The Chicago Teachers Union, an ardent supporter of both Mayor Brandon Johnson and his Bring Chicago Home initiative, hatched a plan to ask its members to recruit high school seniors eligible to vote in the upcoming primary and bus them this coming Friday to CTU headquarters to hear a pep talk on the controversial referendum and then march to an early voting site and, it seems fair to assume, cast their ballots righteously.

That, of course, isn’t how CTU billed this ill-conceived and cynical maneuver. The union called this a “non-partisan voter education forum.” It was an educational exercise, the union said.

“The biggest celebration of youth participating in democracy Chicago has seen in years,” CTU enthused in a letter made public on Monday by the conservative Illinois Policy Institute.

With the campaign for the Bring Chicago Home ballot question itself a sponsor of the so-called Student Power Forum, the event as originally conceived obviously violated the ethics code of Chicago Public Schools. We’re stunned the organizers did not see that.

CPS on Tuesday told us it’s been assured by CTU that the BCH campaign will not, in fact, be a sponsor and will not be part of the agenda. The teachers union’s foundation, however, still is hosting the event at its headquarters. So, thus scrubbed, the event will go on — now as a CPS-sanctioned field trip.

Were CTU simply a labor union and no more, this clarification, so to speak, might be reassuring to those not wanting their kids to be used as pawns in a broader political battle. But CTU these days essentially is a political party unto itself. It is — to employ a lexicon Chicagoans of a certain age are familiar with — the boss.

So any such event hosted by the teachers union will rightfully be suspected of electioneering regardless of the use of terms like “non-partisan,” “civic engagement” and “electoral process” to describe what it’s all about.

Encouraging democratic participation and teaching civics in and of themselves are positive things. Indeed, too many Americans of all ages these days are woefully ignorant of the sorts of civics instruction in which past generations were steeped. So it pains us to urge CPS to scotch this event rather than scrub it.

But that’s what ought to happen given that CTU is at the epicenter of policymaking and politicking in this city. CTU is an enthusiastic backer of the Bring Chicago Home referendum, which would allow the city to quadruple the real estate transfer tax on property sales over $1.5 million (i.e., virtually all commercial real estate sales, including apartment buildings responsible for housing substantial numbers of Chicago residents). The union’s support is not just verbal; it’s providing cash. Lots of it. Hundreds of thousands. As political machines are wont (and free) to do.

The union’s motivation for sponsoring this “field trip” is obvious to anyone not, shall we say, born yesterday. There’s no reason to trust that CTU can run a go-to-the-polls event for high school students without promoting Bring Chicago Home, whether that’s on the formal agenda or not. Full disclosure: This page has urged a “no” vote on Bring Chicago Home for reasons we’ve laid out and won’t repeat here.

It’s worth revisiting CTU’s initial idea for the event, though, disclosed first by the conservative Illinois Policy Institute, an arch-enemy of CTU that appears to have some sympathetic union insiders feeding it information on nearly a real-time basis. The co-sponsors included the BCH organization itself and a nonprofit that provides homeless services and stands to see a substantial increase in city financial support if the referendum passes. Clearly at the center of the whole idea was encouraging students about the initiative’s value and then shepherding them to the polls to dutifully tally their “yes” votes.

As is too often the case with CTU, hypocrisy is on tap. It was a little over a year ago that the union cried foul when then-Mayor Lori Lightfoot’s campaign emailed Chicago Public Schools teachers and asked them to recruit students to help with her reelection bid. CTU was right to do so then. It was utterly inappropriate, and Lightfoot quickly backtracked in the face of justly withering criticism.

Flash-forward to today, and CTU asked the teachers themselves to do this recruiting work within the schools for this Friday’s planned event. “To fill CTU HQ with Chicago’s newest voters we’re going to need the help of staff in High Schools across the city,” according to the CTU letter IPI made public.

So how in the world did CTU’s leadership think it was a good idea to do essentially the same thing Lightfoot did now that it’s in the seat of power, having elected its former member and lobbyist mayor?

Meet the new boss, as someone once sang.

Of course, Friday also is a school day. One might think Chicago Public Schools would look askance at the union representing its teachers encouraging students to skip school to further its political goals. But now, having obtained CTU’s assurances that it will comply with ethics rules, CPS, which Johnson controls via a board made up nearly entirely of his appointees, can say this is all an educational field trip.

What’s discouraging about this gambit is that a citizen’s first-ever vote ought to be an occasion for celebration, however that citizen may choose to vote. We are all for greater participation by young voters. We’ve banged that drum for decades.

Let’s be clear. There’s an intense struggle right now between the progressive interests — led by CTU — that vaulted Johnson into office and traditional Democrats (and even a few Republicans still in Chicago) over the future direction of the city. CTU at the moment is using every tool at its disposal to further its agenda. We get that. Politics is a contact sport.

But leave the kids out of your machinations, CTU. At the end of the day, you’re teaching Chicago’s youth a lesson in politics, but it’s not the one you think.