♪.

Today is an important day here at the Fort. Squeaks and I are going on a science trip, and we'll be gone for a long time.

We’re going on this trip to learn about Cahokia, a place that, almost a thousand years ago, was a huge city. At the time, it was the biggest city in the United States … except the United States wasn’t even an official country yet! Some of what the people who lived in Cahokia built is still there, like big mounds of earth and arrows.

Scientists are studying it to learn more about the ways people used to live, and we’re going on a special research trip to help! But before we go, it's time for us to say goodbye to the Fort, and to you. At least for a little while.

Goodbyes can be hard when they're for a long time, and we might have a lot of feelings -- even some that seem like they're opposites. [Squeaks squeaks]. Squeaks says he feels sad. Me too, Squeaks.

But, how do you know that you feel sad? What did you notice about the way your body is feeling that made you realize you're sad? It's okay to take a second to think about it. [Squeaks squeaks].

Oh, I see. Sometimes when you're sad, it might feel kind of like there's something heavy in your stomach and chest. It makes sense that we feel sad.

We won't be seeing the Fort every day like we used to, or playing in the park we usually go to, or cooking together in the Fort's kitchen. I'm sad because I'll miss those things too. But I’ve also been thinking about all the new things we’ll get to do on our trip.

Did you know there are a bunch of big parks right near where we’ll be living? I can’t wait to check them out! We can play ball games, go on the slides and swings, and even have picnics when the weather’s nice. [Squeaks squeaks].

Yep, just like what we do here! There are also lots of farms nearby where we can visit horses and cows and chickens, and even get fresh vegetables to use when we cook together in our new kitchen. And our friend Ruffles the Squirrel lives pretty close, so we’ll be able to see her all the time! [Squeaks squeaks].

You’re feeling something else? What do you think it is? [Squeaks squeaks]. That’s okay — sometimes it can take a minute to figure out what we’re feeling.

Let’s start with this: what does it feel like in your body? [Squeaks squeaks]. Hmmm…. Squeaks says his heart’s beating faster, but in a good way.

Do you think … you might be excited? [Squeaks squeaks]. Me too! It might seem strange to feel sad and excited at the same time, because they’re almost like opposites.

But with something big, like our move, there can be lots of parts to it, and it makes sense that we would have different feelings about those different parts. There’s the part where we’ll be away from the Fort, and the places and people we know really well. And that makes us sad.

But there’s also the part where we’ll be in a place with lots of cool new things to explore, and different people to get to know and make friends with. And we’re excited about that! All different types of feelings are important.

But I know that when I’m feeling sad about the move, thinking about the things I’m excited to do in our new town helps me feel better. Even though you won’t see new videos of us here while we’re gone, Squeaks and I will still be out there, learning and exploring like we always do. We hope you’ll keep learning and exploring, too!

Over the last few years we’ve done tons of projects and experiments and learned about all kinds of different things, and I bet you haven’t seen them all yet! You can check out those videos, or rewatch some of your favorites. In a few days, we’ll be making one more video with some of our favorites for you to check out.

And if you try some of the experiments for yourself, or learn something new you want to share with us, we’d love to hear about it! Just grab a grown-up and send us a message at kids@scishow.com, or leave a comment below. In the meantime, thank you for joining us on our adventures here at the Fort, and for all of the wonderful messages and questions you’ve sent over the years.

Squeaks and I have learned so much from all of you, and we can’t wait to start our next adventure! ♪.