You are way off the mark! Einstein's theories of Relativity (Special and General) superseded Newton's theory because they explained observed phenomena that Newton's could not. That is the way science works. (and ID doesn't) You have heard of the Michelson-Morley experiment, haven't you? Read up on it and you won't be lost in the ether.
No, you are mistaken. Newton's three laws are a special case, and continue to be useful until you begin to approach light speed. A recent poll of British scientists voted Newton as the greatest scientist of all time, and Einstein second.
I majored in physics at Harvard before switching majors, and I can assure you that we studied differential equations (mostly Newton's idea) and classical dynamic theory as well as Einstein.
Not to teach Newton in school because he is "outmoded" would be the height of stupidity. F=MA continues to apply in the practical world.