The relationship you were referring is now clear to me. The 14th amendment protects our basic rights, which in this case it specifically relates to parents right to teach their children in the language they wanted.
In our current time the gay community has been fighting equal protection under the law. The 14th amendment protects that right.
I think if the decision had been different, foreignness would not been welcome into this country, and any one that maybe be “threating” to the culture at the time would be discriminated. We would possible not have the melting pot that we have today, schools