I would disagree with you. Specificly the treaties that Bill Clinton signed on behalf of the United States, if ratified by the Senate would specificly place these rights in the hands of the government.
Under the Constitutions Supremacy Clause of Article VI Section.2, all treaties made, or which shall be made, under the authority of the United States, shall be the supreme law of the land; and the judges in every state shall be bound thereby, anything in the constitution of laws of any state to the contrary notwithstanding.
In Missouri v. Holland, (252 U.S. 416), the U.S. Supreme Court held that under the Supremacy Clause a treaty made by the President, with concurrence of two-thirds of the Senate present at the time of voting, would become the supreme law and take precedent over contrary state laws. Thus, the U.N. Convention would constitute legally binding law in all 50 states. Otherwise valid state laws pertaining to education, the family, etc., which conflict with the provisions of the treaty will be subject to invalidation.
So unless there is a specific enumeration of the rights in the Constitution, they can be "given away" by treaty.
See the following for more information:
http://en.wikipedia.org/wiki/Convention_on_the_Rights_of_the_Child
http://www.hslda.org/docs/nche/000000/00000021.asp