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.