I hope people don't believe that there was ever a real teacher making that speech.  It have as many versions as the Bible.  BRUHAHAHAHAHAHAHAHAHAH!  It's a hate speech anyway to say that only one race is welcomed especially in a public school.  They named the different races in one version.

See here http://www.snopes.com/politics/soapbox/principal.asp  to see what Snopes says about it's origin, read the different versions and how it is connected to radio white supremacy hate.