Sigrid seeks to answer the question "What's a borough?" In doing so, she talks about how New York City got its start, and also about the surrounding counties that played an important role in its development. In this video, you'll see 18th- and 19th-century maps of the area.

Sigrid describes the first part of her trip from Long Island to New Jersey, taking a moment to tell us about the famous Verrazzano Narrows Bridge.

Sigrid traveled back to the U.S. recently to visit her family. She talks about her trip and takes some "detours" to share what she learned about some of the places she visited. She also happened to go to Mexico, where she shot this introductory segment.

Most Americans don't realize how Columbus Day came to be a national holiday, but it actually doesn't have that much to do with Christopher Columbus, and we might even recognize a connection to present-day events. To recall something Mark Twain once supposedly said, "History doesn't repeat itself, but it often rhymes."

Columbus Day has always been a controversial holiday in the United States. In this video, Sigrid goes back in time to get some historical background, which sheds a new light on its significance.

What do people traditionally do on Memorial Day and Labor Day? Let's find out.

Sigrid talks about two important US holidays, Memorial Day and Labor Day. They are quite different in what they commemorate, but they're combined here because many Americans see them as bookends to the summer season.

Let's have a look at which countries are members of the European Union and where they are on the map.

The European Union has been in the news a lot lately, so let's take a look at what it's all about. What is a "union" and what's the purpose of this one?

We continue to explore the phenomenon of hurricanes. Why are they so dangerous? And do they serve any purpose?

In recent years, we've seen an increase in the intensity of tropical storms and hurricanes due to global warming. But how and why do hurricanes form? Sigrid provides a basic explanation of this phenomenon.

Sigrid explains how a spelling bee normally proceeds. There are fixed rules and there are options.

Ever year, the winter solstice comes on December 21 in the Northern Hemisphere. Not only is it the first day of winter, it's a turning point, as the days will then get longer.

Sigrid talks about "The Elementary Spelling Book" by Noah Webster, which was the basis for the American English dictionary and a big part of the development of spelling bees in the United States.

Let's find out more about an American activity aimed at school kids: the spelling bee. What is it and how does it work?