As long as we keep the racism alive, we'll never get to the point where racism doesn't matter. You don't need to beat kids over the head with it to get them to understand that blacks used to have it tough. It's great that Justice Marshall was the first black Supreme Court justice. Neato. Tell it, then leave it. We don't need a list of first black this and that. How about just treat them like people, not like people of color. History worthy accomplishments should be noted for their history worthiness, not for the color of the person who did it. It's time to stop the identity politics. We'll never have a color blind society until you stop reminding people what color they are. Stop the hate. It's not revisionist. It's choosing to focus on the positive, and not rubbing people's noses in the negative.
Cesar Chavez is not history worthy for children. Teach about him in college to people who give a crap, but he is of no real significance otherwise. Maybe mention him when talking about unions and their place in history, but he gets far too much coverage simply for being a minority. He's a footnote in history, and nothing more. The only reason he is mentioned is to support the identity politics of "Hispanics" in some misguided attempt to keep them interested in the classroom and to keep the La Raza rabble-rousers off of the administrators' backs. It's time wasted to check off a political box.
Reconstruction is important because it was an actual period of history that affected the country as a whole in a significant way. You can certainly talk about what happened to slaves between emancipation and Jim Crow, but to keep harping on it the way they do is simply ridiculous. Teach history, not identity politics.