I had a similar experience, in a US high School, or "her"story professor, a 90lbs vegan with a penchant for wearing leather sandals taught us, Ho Chi Minh was like Thomas Jefferson, when not reading Upton Sinclair, or Howard zinn, we had to read Anthony Robbins "Diet for a New America".
I recall we had to role play and act out the Kent State Shootings in our class. I was assigned to be a protestor, I complained and said that I was a pretty conservative, but was assigned to play a protestor anyways. I started a chant "what do we want, Peace!!, when do want it now!!, We WILL FIGHT for the ideas of Mahatma Ghandi!!!" at which point he wasnt amused and sent me to the principal's office.
Later we had to watch "Born on the 4th of July". I remember the second time I was kicked out of class. He paused the video and asked the class why the protestors were wearing red arm bands. No one wanted to answer the question as this guy had a notoriously short fuse, so he re-asked the question several times, before I put my hand up and answered. The protestors are wearing red arm bands in this scene, because the NAZI's wore red arm bands, and they wish to compare the authoritarianism in our government to the NAZI regime. He begrudgingly said that was the answer he was looking for, then I piped in, "Which is odd because most of the protestors would have considered themselves leftist or liberal and socialism was very popular among them, and the NAZIs were socialist."
I was told the NAZIs werent socialist, and countered "in German it is abbrieviated NADSI or National German Socialist Workers Party".
Long story short he kicked me out again, I was proud, I was "kicked out for my views on 'Nam"
I suspose whether or not your experience with extreme liberals or conservatives in school had a lot to do with location and demographics.