I gather Texans are just enamored of all things Canadian ~ snow and stuff ~ so they've tried it.
It's stupid. We've known for thousands of years that linguistic minorities must still learn the language in general use as well.
Bilingualism was not an experiment that Belgium and Canada just decided to tryout one day. The people who speak English, French, or Flemish(Dutch) happened to live there before there was a Belguim or Canada. You could argue that the uniting of two distinct nations into one is a failure, but this is not bilingualism that is practiced in France or the US.