"In fact, evolution can be precisely defined as any change in the frequency of alleles within a gene pool from one generation to the next."
- Helena Curtis and N. Sue Barnes, Biology, 5th ed. 1989 Worth Publishers, p.974
Biological evolution is a fact. Facts do not go away when scientists differ over the theories. The theories of evolution are science’s explanation of the mechanism of evolution. Just as the existence of electricity is a fact and the mechanism of electricity is electrical theory. There may be many different explanations for how electricity works but the accepted theories allow us to make use of the "fact" of electricity. For those interested, an excellent on-line resource can be found at http://www.talkorigins.org/.
I fail to understand why some people think that you have to choose between religion and science. That one must be true and the other false. Of course, if one insists upon a literal interpretation of Genesis or the Rig-Veda or of any other holy script then... yes, the fact of evolution contradicts the spiritual texts. Just as the fact that the earth orbits the sun and the fact that the moon is not a great light in the sky but actually reflects the light of the sun contradicts spiritual texts. Scientific discoveries are often at odds with literal interpretations of holy texts.
The practical application of science has improved our lives through advances in such things as sanitation, medicine, gene therapy, agriculture, etc. Can we afford to deny our children an education in scientific discoveries that may contradict a spiritual teaching of our respective religions? Shall we ban everything that contradicts anyone’s religion or shall we choose only what suits the majority and deny the others? When we are done, will there be anything remaining to teach?