franny,
Welcome to EVC!
why not make it clear that it is not a law and that it is not factual.
A "fact" in science means something that is so evidentially well supported that to withhold consent is unreasonable. By contrast there is no such thing as a 100% absolutely known conclusion in science, it is all tentative to one degree or another.
Evolutionary theory is supported by a wealth of interdisciplinary evidence that all points to the same thing, & as such is as much a fact as anything else considered a fact in science.
Mark
There are 10 kinds of people in this world; those that understand binary, & those that don't