Hello, I'm a long term lurker, first time poster here, so I hope I have followed all of the guidelines. I enjoy the well curated and civilized discussions that occur here in this sub. Quick background, this past year, I got my first job teaching high school math at a small Catholic High School in the southern United States. As it is a small school, there are not a lot of teachers or resources so I was drafted into teaching the AP US History course. The majority of my students come from conservative religious educational backgrounds and as a result, the history they've learned is incomplete for lack of a better term. To be clear, I'm not here to debate this issue, just looking for an answer and guidance.
When we first started our class, we began by discussing Christopher Columbus and his voyages, but in our discussions, it became clear that they had really only learned the hero side of Columbus and the myth that seems to have formed around him. None of my students were familiar with the Norse colonization of North America in the 10th century.
We've just started the American Revolution and we were discussing George Washington, particularly the story of him cutting down his father's cherry tree. From what I was able to gather, the myth was created later by one of Washington's biographers, a man named Mason Locke Weems. I recognize that there are a lot of historical inaccuracies that have permeated history education, so what I am trying to learn is was it an organized effort to do so? Was it a specific period of historians who interpreted events to fit a hero narrative or was it more like the cherry tree example, in that it was isolated cases that snowballed throughout time? If it was an organized effort, was the goal to make money selling books or tell a specific narrative?
Teaching a US History class is not what I expected to be doing this year and while I've taken enough courses in college and read enough to be comfortable with the material, I want to make sure that I am not doing my students a disservice by leaving out important details or presenting a "curated" view of American history. I firmly believe that they need to fully understand the history of the US in order to be informed citizens and I want to make sure that I am doing all that I can in order to prepare them for such.
This community is, I'm sure, full of other educators so any guidance you can offer about avoiding future pitfalls in the curriculum would also be really useful if that would be allowed in this sub. Thank you for your time and all that you do here!
Edit: I want to make sure that it is clear that I am not criticizing any particular form of education. All of them have their own particular strengths and weaknesses, I am merely sharing my situation to provide context.
In case you haven't seen it, this response to a previous question about history in American elementary schools provides some good context to your question. I'll offer the historical record is somewhere between a snowball and a deliberate campaign, and a little bit of both. There's a number of factors that contribute to what you're experiencing.
For good or for bad, there isn't a lot around American education at the national level that is actually organized, which is why the responses to the question above focus on particular states. What you're asking about and what many of the responses are speaking to is generally known as the "grammar of school" - it's a collection of practices, events, and routines that schools do because they're seen as a part of what school is supposed to be. At the elementary level, a lot of what happens in schools, especially elementary schools, is organized around the calendar. (Teachers in 1840's wrote in their journals about using holidays and events to inform their curriculum - it's a well-established school practice.) This includes things like turkey hands around Thanksgiving and marking holidays like President's Day with events that memorialize the early presidents (and Lincoln.) So, there is a fair amount about school today that's passed along through repetition and tradition.
Next, given the teaching force has long been overwhelmingly white and female while those in charge (school, district, and state leaders, curriculum writers, textbook authors, and school board members) have been white men, whiteness has informed who gets celebrated and taught in American schools. In effect, Washington reflects an archetype and cipher of said whiteness: he was an alpha, a patriot, a leader, a husband... an American man (a framing that allows adults and children to ignore the unpleasant bits.) This same whiteness informed the rise of Columbus as a touchstone: he was curious, an adventurer, a man who took charge and set out to explore (a framing that allows us to ignore the bad bits.) In effect, if there's one narrative at work, it's one around white supremacy.
So, we've got all that tranditions and whiteness combined with "recitations", the primary form of assessment for generations. Young people would hear or read content, memorize it, and recite it back. Generations of young people were raised with the idea American history began with our first president. Memorizing the names of presidents and being able to recite them back was a routine part of learning in schools (although history as a separate subject wouldn't become the norm until the late 1800's.) (The endearing love of recitation helps explain why millions of Americans, young and old, automatically know the last word to to the saying, "In fourteen hundred ninety-two, Columbus sailed the ocean ....")
Bring all of that together and the seeds are planted for George Washington to be the alpha of American history. To be sure, textbook authors were aware of other explores. Illustrated School History of the United States and the Adjacent Parts of America, From the Earliest Discoveries to the Present Time, authored by George Payn Quackenbos, references, and dismisses, them in a single paragraph:
On this subject we have conflicting and uncertain accounts. According to Welsh historians, the Atlantic was first crossed in 1170, a. d., by Ma'-doc, a prince and hero of Wales; but the Norwegians, on stronger evidence, claim this honor for one of their adventurous sea-kings. In the ninth century, both Iceland and Greenland were discovered and colonized by Scandinavian navigators; and about the year 1000 a. d., if we may believe Ice-land'-ic manuscripts, a vessel driven by storms southwest of Greenland arrived at the continent of America. If this be true, it was no doubt the barren shore of Labrador that was reached; and so unimportant was the discovery considered that it was soon forgotten.
So, in effect, Columbus was the first and most important explorer and Washington was the most important American. Finally, combine all of that with parochial education and you're not likely to find a progressive approach to American history. Virtually all Catholic schools on the east coast have their roots in activism by the Church and parents in the early 1800's. Dissatisfied with the progressive direction the Protestant or secular led nascent public schools were heading, they sought to create an option for their children.