One of my biggest challenges in educating the public about American history is providing a proper chronological frame of reference to help them better understand whatever it may be that I am speaking about. This is of course more difficult in some situations than others, and obviously it largely depends on the audience and the topic being discussed.
For example, it isn't a real struggle to get 4th graders to understand that the Revolutionary War happened over 220 years ago; they usually accept what you tell them at face value as the truth. But, to get them to truly understand how different things were 220 years ago versus today, and what all has happened in between those two historical points is much more of a challenge. Getting them to understand that communication worked at a snail's pace and that travel was largely limited to walking, riding a horse, or sailing on a ship is difficult because it is so foreign to their modern understanding. Then, getting them to fully understand the historical significance of something like the Revolutionary War and what that means to them today is a real challenge. But, no matter what age one deals with, seeing that light bulb go off when they make that historical connection is indeed priceless.
I think one of the most important things in teaching history is to get one's audience to understand that, although events happened long ago, and personalities have long passed away; many of those events and those past peoples' actions still have an effect on us today in the present. Helping people make personal connections to the past is what makes all the difference.
Making connections to the past can be done in many ways. Some people can relate better from a generational viewpoint. Explaining how something worked in a person's great-grandparent's day helps provide a historical frame of reference. Some people relate to the past by visual comparisons. Looking at images or photographs that type of person can compare the clothes, buildings, and other things of everyday life and then come to a historical connection. Some people like looking at the actual material culture of past people. I think that is one reason why museums are so beneficial to the public. Museums provide a informal learning environment where people can spend as long or as little time as they like looking at "old things" and not be under pressure to learn as they might be in say a classroom environment.
History museums, for both practical and educational reasons, have stepped up their exhibits in the past 10 to 15 years. It is no secret that museums compete with entertainment venues such as movies and sports for the public's time and money. To better compete with these other attractions they have incorporated more technology and interactive exhibits to make learning more fun while not sacrificing their educational value or credibility.
If you haven't been to a history museum in a while, do a little searching on the Internet and find something that looks interesting to you personally, and then go and experience and learn...make those connections to the past...that's what they are there for.