I think that it is very important to separate science from most other areas of education. In science, the basic knowledge base, and thus the half-life of knowledge is contantly changing. It is inevitable, particularly during the earliest phases of teaching a subject where many things are simplified to ease introduction, and when looking at the state-of-the-art where the knowledge base is being expanded, that there will be errors.
But... this is also one of the greatest strengths of science. Unlike religion, science has a builtin correction method. It is the publish, review, replicate and independant verification process that is the hallmark of science.
Many other areas, for example history, really do have many flaws. Those flaws though usually stem from a parochial viewpoint during the teaching process. Unlike science, instruction is history really sucks. Speaking primarily of US public schools, we do a lousy job of teaching where we failed in the past. The result is that we continue to make the same mistakes over and over again.
Aslan is not a Tame Lion