Most of science and "scientific facts", if you want to call them facts, but I don't believe that scientists use that term, is based on something that is observable and repeatable, so if there are speculations and presuppositions, they are validated by the experimental test. For example, nobody knows which way electricity flows, positive to negative, or negative to positive, but it doesn’t matter, electricity flows because we can test it by flipping on a light switch. The same thing with universal gravitation, we can test that. Scientists might not understand everything about gravitation, but we can test it with observable, repeatable experiments.
Not so with evolution. We can’t observe and repeat the beginning of the universe, earth and millions of years of evolution. We can’t observe and repeat the origins of man in a lab, at least not yet, if ever. Yes we can observe that creatures change and adapt to their environments and if you want to call that a “fact” then that is fine, I won’t argue against that. However the origin of man is forensic science, not observable and repeatable science.
Here is the problem. If there are gaps in what science can duplicate through observable and repeatable experimentation, such as the origins of man, it isn’t valid to say that a natural answer is the only possible answer. When people come out of school maintaining the position that evolution is a fact, and then calling creationists anti-science, then that is an obvious sign of indoctrination. What is anti-science about asking for science to follow the scientific method, by showing the observable part of man coming from some other creature? What we observe is what the Bible teaches, that there are clear seperations between organisms, so there are other valid alternative to evolution explanations as to how man got here.