The theory of evolution suggests a process by which all living things have developed from primitive organisms through changes occurring over billions of years, a progression including the most advanced animals and plants. Evolution suggests that perhaps once upon a time the world was nothing but atoms and they just happen to fall in place over the years to create the world as we know it today. Intelligent design suggests that a divine force has guided the creation of everything we have today. No one likes to be wrong especially when dealing with their eternal fate, so the two ideas have shown to be rather controversial in the past and still to this day.
Biology text books are for the study of Biology, thus the name. Darwinism is a theory, a theory that in many eyes contradicts religious beliefs. Perhaps it is better reserved for a class on theory. The concept of Darwinism I"m sure has played an important role in biological research but why must it be that only the strengths supporting the theory be presented in Biology books. Is "intelligent design" not also a cornerstone theory for biological research? Both sides perform research to support their individual beliefs in hopes that they are right. Feeling that in the end should they be wrong, may god have mercy on their soles, or on the flip side, hopefully they had enough fun despite their restrictive religious beliefs. Regardless of ones religious stance the teaching of Darwinism should be taught for what it is a theory, which means it should be taught thoroughly, underlining supporting details as well as dissenting. The book design should be done in such a manner that a religious as well as non-religious person can learn about Darwinism in school and leave with the same sense of certainty for their beliefs as before they walked in. The books should not favor either view instead they should have a diplomatic approach toward such matters.