"I was taught in my Social Studies (late 70’s) from the text book (for which I am still hunting) in the Great State of Texas ... BOTH parents had to be citizens to be Natural Born with the founders and those here at the Revolution grand-fathered as citizens."In this case, your great state failed you. That two-parent requirement is not in the Constitution. Doesn't exist.
Stop misinforming people. It is not written in the Constitution because in 1787 there was no need to define something so obvious.
The "Two-Parent requirement" is not a requirement, it is the unavoidable consequence of the American Father requirement. The woman became automatically a citizen when she married an American Husband, so it reduced to a "two-parent" citizenship situation.
In fact, it was always a "one-parent" situation, so long as the person who had the citizenship was the Father.
This is also reflected in English Law, where only an English Father could pass on "natural born subject" status.
If you doubt what I say on this, take a look here at the Naturalization act of 1790. It specifically says that if a Child is born abroad to a non-resident father, (meaning someone who isn't intending to become a citizen) they cannot have American citizenship.
Provided, that the right of citizenship shall not descend to persons whose fathers have never been resident in the United States: