In high school i was taught that evolution was a fact in some ways such as dating systems, overall fossil records that i dont know that correct phrase but i think maybe transitional fosils that prove how animals evolved, and just overall in general that scientific theories are basically factual even though they are not a law.
I'd like to reiterate on this point.
And as Modulous pointed out, school systems are very constrained in their time. I mean consider your own high school experience, how in depth do you feel they treated science courses, or even math or literature courses? For example, consider an american literature class, there is aproximately 400 years worth of american literature to examine, and if you want to get at it even more you have to look back a little bit at european literature, how well can 36 weeks compress 400 year's worth of literature plus background information? Or even general biology, keep in mind you have 36 weeks... and theres alot of material to talk about! Consider, cellular processes, aerobic respiration, anaerobic respiration, glycolysis, photosynthesis, then theres just plant cells and animal cells and all the little cell organelles, then you have things like anatomy and physiology (bones, muscles, nerves, reproductive system, cardiovascular system, waste system). then you can talk about DNA, and genetics... I mean right there is 14 topics to talk about and each of them a huge amount of information buried in them! Consider that at college level there are semester long courses just devoted to the study of genetics at the undergraduate level and there are even graduate level courses that go even more specific!! And high school classes are expected to teach biology in the span of 36 weeks?
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