Thank you! I will check it out. I can’t imagine what keywords you had to think of to search for it, but kudos for that! The movie gave me the chills, and the poor elderly teacher just broke my heart. Unfortunately I missed it in its entirety, but thinking about it now, it could be a pre-1984 orwellian play. Heartwrenching.
I searched on "book and play communism taking over a classroom of young kids". It was the fifth link.