One evening, back when my daughter was in high school, she showed me the map that her teacher handed out in geography class. It was a schematic drawing, black lines on white paper. The outside line enclosed the area of Israel, the West Bank, Gaza and the Golan Heights. The inside lines divided it into geographic regions that the students were supposed to label – Samaria hills, coastal plain, and so forth. My daughter had stopped the class with a question. "Where's the Green Line?" she'd asked the dumbfounded teacher.

The map was a political statement: The outside line was a political border. There were no other political borders, no distinction between Israel and occupied territory.

It so happens that the high school was religious, and that the teacher lived in a settlement. That's irrelevant, since similar maps can be found in textbooks throughout the Israeli educational system. Politics, of a particular sort, suffuses the schools.

I mention this because the new school year just opened with two public fusses about educators expressing political views. In Ashkelon, the mayor joined a parents' association that tried to block the appointment of a new principal for the city's School of Arts. Her purported offense is that 13 years ago, she signed a petition in support of soldiers who refuse to serve in the occupied territories.

And in Ramat Gan, the mayor – a former principal – has joined parents in demanding that high school history teacher Herzl Schubert be fired. His transgression is that he has allegedly been spotted in a video of a demonstration at the West Bank village of Nabi Salah. Every Friday, villagers and supporters protest the takeover by settlers of a spring on their land. The army has declared the area around the spring a closed military zone – for practical purposes, backing up the land grab.

Open gallery view Protest in Nabi Saleh, September 4, 2015. Credit: AFP

Mayor Yisrael Zinger says Schubert "attacked IDF soldiers." As far as I can tell, watching and re-watching the clip, this is the mayor's imagination. The video briefly shows the figure who may be Schubert enter the camera's frame while Palestinian women try to pull a terrified 12-year-old boy from a soldier attempting to arrest him. The only physical contact involving Schubert (if that's him) is when another soldier shoves him. More accurate right-wing screeds say he should be fired simply for being there.

The vigilant parents, let's be clear, are upset about the stance taken by Schubert on his own time, outside the classroom. Nonetheless, the ORT network, to which the school belongs, says it's looking into the matter.

But I can testify that teachers do express political views inside the classroom. I have long parental experience – starting when my eldest was in kindergarten and one of his teachers devoted a good part of a morning drilling into her five-year-olds the catechism, "The Cave of Machpelah does not belong to the Arabs."

Later, my youngest was in third grade when Likud was about to hold its internal party vote on the disengagement from Gaza. Her teacher made an addition to the class's morning prayers: asking the Almighty to sway members to vote no. She devoted a class to that message as well.

In the winter of 2006, one of the teachers at my son's high school left during the school day with two students for an extracurricular activity: joining the crowd of demonstrators at the outpost of Amona, trying to prevent police from carrying out a Supreme Court order to demolish houses built on private Palestinian land.

These are just three of the incidents that stick in my mind. What bothered me wasn't that the teachers had political opinions. It wasn't even that they expressed them to students. It was that they regarded those views as the unexceptional, consensus default position.

Some readers will say I can't complain, since I sent my children to religious schools. This attitude is mistaken. It accepts that one highly nationalistic reading of Judaism is the correct one, so that if the state has religious schools at all, they will inevitably teach that perspective.

Worse, it ignores the nationalist messages pervading the entire educational system – even in the purportedly enlightened enclave of Greater Tel Aviv. Those textbooks with maps in which the West Bank is already part of Israel are used everywhere. The curriculum is political when it devotes too little time to how democracy works. Taking 12th grade classes to Poland for an emotional lesson on the Holocaust while the schools starve for money is political.

To be fair, the choice of what to teach in history and civics is always political – but much more so when the political message is submerged, when it's treated as being neutral and normal. In that reality, a teacher who goes along with treating the occupation as invisible is supposedly not engaged in politics. A teacher who challenges the injustice of the occupation – even on his own time or hers, outside the classroom – stands out, and is treated as dangerous. The mayor rages; an investigation is needed.

The young people of Israel have actually begun the school year with a stinging lesson in politics, administered by mayors, parents and media organizations that joined the witch-hunt: Don't dissent. This is all the more frightening because the people who taught the lesson believe that they are keeping politics out of the schools.

Gershom Gorenberg is the author of "The Unmaking of Israel" and "The Accidental Empire: Israel and the Birth of the Settlements, 1967-1977." Follow him on Twitter: @GershomG.