Currently there are the four core classes in the United States system (math, history, english, and science). Within those, teachers try to hone in on critical thinking skills, but it often proves ineffective. Looking at how people communicate, especially in a class type setting, ideas are not being discussed. Information is simply passed from one person to another.
Rather than accepting everything that one hears, let us learn early on to never stop questioning. Consider the why, the abstract ideas, and have a class where students don't have to hold their tongue against a teacher's ideas.