Contrary to what you may have learned in your government mandated evolution indoctrination classes, most creationists do not dispute the fact that plants and animals evolve. Humans have evolved countless breeds of dogs, cats, horses, cows, vegetables, fruits, etc. No one disputes evolution. What is disputed is the theory of evolution mainly because it includes the idea that life randomly spawned out of a pool of liquid. Today humans are creating simple life forms, proteins, in laboratories. We are creating and evolving life forms. This means it is indisputable that an intelligent creature could design another life form. Just as we breed dogs for different characteristics, an intelligent designer can do the same for the new life form.
Darwin had a good idea for the 19th and 20th centuries. That was when we thought a cell was blob of simple jelly so the idea single celled creatures came oozing out of some slime made a lot of sense. Everyday we find new things about how complex a single cell is, that the idea that it happened randomly becomes more far fetched every day. We are talking about lots of time here, but how often has a random rockslide ended up building a car? Thats the kind of unlikehoods we are looking at.
Where you stand on this issue determines if you believe we are here for a purpose or reason, or whether you think life is just a random thing, and there is no (big picture) purpose behind us being here other then 'survival of the fittest' so you can pass down your genes and continue the evolution of life. For many people, including me, the answer to this question determines our outlook and actions on a daily basis. That is why I think it is so detrimental that the state is forcing one viewpoint on our youth.