Half the time was wasted

Back when I was at secondary school in the late noughties, one of the teachers, a science teacher would often waste half the lesson ranting on about how pathetic we are compared to kids in schools like Japan or Poland, the irony couldn't have been any greater when he said we aren't learning anything but then prevented us from learning for half the lesson when we were forced to listen to the ranting.

I'm not sure where I stand with Tesco on this matter. Can I sue them for all the times this teacher wasted half of the lessons with these rants that had no real context to them?