Why both זו and זה are correct? Dosn't שטיפת מח should be refered only as זו/זאת?
זאת is for שטיפת (feminine), זה is for חינוך (masculine)
sorry, I meant at the beginnig of the sentence
בטח, זה מה שאומרים בכל הכתות... :)
That's because all the teachers have gone through Teacher's Colleges and get their teaching certificates if they pass the same tests.
It is interesting, guys. The parallel translation is washing of mind.