The problem with excluding alternative (competing) explanations is that many of them are also scientific and equally valid but not the orthodoxy, and therefore the Establishment will suppress all competing views -- because they threaten the status quo view of which they are its high priests (experts). But more and more, there will be revolutionary paradigms that dispute most of what was previously known. However, the teaching hierarchy (NEA, Board of Education) will suppress superior knowledge in favor of invalid knowledge -- because that is what they were indoctrinated to believe is the truth, though the state of the art in every field is highly dynamic and changing. That is the skill set one wants students to learn and not simply accepting what their teachers tell them is the truth and ONLY truth.
When students get that kind of education and then get out into the world, many start to flounder and fail because what was told them and they took on faith as the scientific truth, was only blind faith, and not the questioning of all authority -- including the teachers.
In order to be superior choosers in their lives, children must be exposed to choices to learn to make better choices -- and not be sheltered from that experience because somebody claims to know the REAL TRUTH and others don't have it. That's why our schools ARE such failures. They don't teach the students how to think -- but only what to think, ie., political correctness, so they become more dependent on teachers and more vulnerable to demagogues. Then the unions stick a sign in their hands and tell them what to chant -- and how high to jump, and that's all they know, fancying themselves as those "in the know.."