Now that you mentioned it, the antebellum period gets skipped over or fast forwarded a lot. It’s like boom and the civil war happened after independence. Maybe they don’t like to talk about the slave economy in places or the civil war is just more impactful and interesting.
And antebellum history varies state by state, the country was pretty different place to place so perhaps that’s why they don’t teach it as whole much. In Texas we learned a lot about the Texas history during the time, like texas revolution and succession after independence.