This is neither history nor patriotism. An uncomplicated celebration of American greatness flattens the past into a parade of platitudes devoid of the context, conflict, contingency, and change over time that are central to historical thinking.
The history of America is incredibly complex, and an oversimplified and idealized narrative does a great disservice to the educational curriculum. History needs to acknowledge the complexity and fallibility of our nation's past in order to learn from it.
There are, however, standards that ask students to “identify Afro-Eurasian trade routes and methods prior to the development of the Atlantic slave trade” with the clarification of “instruction includes how slavery was utilized in Asian, European and African cultures,” and ask students to “examine the condition of slavery as it existed in Africa, Asia, the Americas, and Europe prior to 1619.
There definitely seems to be an agenda behind the inclusion of the history of Afro-Eurasian slavery, and the omission of the history of African civilization. It not only ignores the history of an enslaved people, but it shifts the narrative around slavery to effectively "everybody was doing it".