Squeaks and I had an interesting adventure this morning.

Last night, it was snowing when we went to sleep, and when we got up today there was

a bunch of snow on the ground!

There's this great hill in the park behind the Fort, and Squeaks wanted to go sledding.

So we went out there, pulled our sled up to the top of the hill, and pushed off.

We started to move a little bit, but then, before we could get very far … we stopped!

Now, I don't know about you, but to me that seems like kind of a silly sled ride.

We barely moved before we got stuck in the snow!

What do you think, Squeaks?

[Squeaks squeaks]

Yeah, it was kind of disappointing

But even though our sled ride this morning didn't work so well, I bet we can find a

way to have an awesome sled ride when we go back to the park.

Because with science, we can figure out why we went so slow, and how to get ourselves

zooming down the hill instead!

When we're sledding, we want to move forward as fast as we can.

And there are a couple of easy ways to help ourselves do just that.

One thing we can do is push off really hard at the top of the hill to give ourselves more

speed right from the start.

We can also have more weight on the sled, which will keep us going for longer before

we stop — like how it's much harder to stop a heavy bowling ball that's rolling

toward you than it is to stop a lighter soccer ball.

[Squeaks squeaks]

That's true, Squeaks!

We were already doing both of those things this morning.

We pushed off really hard at the top of the hill, and with Squeaks and I both on the sled,

there was plenty of weight to keep going.

But that wasn't enough!

We still didn't move very fast, and we stopped pretty soon after we started moving.

That's because there was something that was slowing us down — it was pushing back

on us and stopping us from moving forward.

Something that pushes or pulls is called a force, and the force that was stopping us

from zooming down the hill is called friction.

Friction is what makes it hard to slide things across each other.

There's lots of friction if those things are rough, and less if they're smooth.

Have you ever noticed that when you're wearing socks, it's much harder to slide your feet

across carpet than it is to slide then across a wood floor?

That's because of friction.

Carpet is pretty rough, so there's more friction between your socks and the carpet

than between your socks and the smooth wood.

The force of friction pushes hard against your socks as you try to slide them across

the carpet.

And the same thing happened with our sled, Squeaks!

Our sled is made of wood, so it's pretty smooth.

But the fresh snow from last night is still soft and powdery, and that was making it hard

for our sled to slide across it.

Instead, the snow kinda bunched up underneath us, and there was lots of friction slowing

us down after we pushed off.

That's why we didn't go very fast or far before we stopped.

So, Squeaks, if we want to go really fast next time, what do you think we should do?

[Squeaks squeaks]

That would be one way to do it!

We could wait a few days until the snow on the ground is much more packed down, so it'll

be hard and smooth.

But we could also just pack it down now!

We can go back to the hill and stomp on the snow for a while, then smooth it out to make

a nice track of hard, packed-down snow for our sled.

It'll be a little more work before we can start sledding, but I think it'll be worth

it!

How about you, Squeaks?

[Squeaks squeaks]

OK, let's do it!

(♪♪♪)

Wow, that was awesome!

We went back to the hill with our sled and ran around on the snow for a while to pack

it down into a smooth track.

Then, we went up to the top of the hill, pushed off, and … zoomed all the way down to the

bottom!

With the smooth, hard snow, there wasn't as much friction pushing back on the sled

after we pushed off.

So we kept going faster and faster!

[Squeaks squeaks]

Yeah!

Let's go do it again!

Thanks for joining us!

If you want to keep learning and having fun with Squeaks and me, hit the subscribe button,

and we'll see you next time here at the Fort!

(♪Outro♪)