There is a a pretty clear genetic picture that pretty much answers your questions and it wouldn't be considered indoctrination.
One thing for sure, modern day homo sapiens usually differ in the parts that interact with the environment. This includes skin color as well as the digestive system...there are countless examples.
But if you cut open different races and put the body parts on a table, you wouldn't be able to tell an Asian heart from an African's heart or a Caucasian (white skin from Europe) heart.
I think we are very much the same in areas that do not interact with the various different environments, but those environments have contributed to differences in both appearance and digestion.
Like I said, the genetic picture of man's migration out of Africa is getting more and more clear, including the races that intermingled to form what we are today.
You're right about not always getting the whole story in school, but to be fair it is a pretty long and detailed story.
God's work is mighty.