Ramps With Different Surfaces (Outdoors)

Compare how an object moves on two different slanted surfaces.

Materials

a variety of balls of different sizes and weights—beach ball, kickball, tennis ball, ping pong ball, Wiffle ball, golf ball, football, etc.,
camera or video camera
“Different Surfaces and Objects” chart

Key Science Concepts

The motion and speed of a rolling or sliding object is affected by the shape and texture of the object and the texture of the surface on which it is rolling or sliding.

Vocabulary

Encourage children to use words such as incline, ramp, texture, and surface, descriptive words such as faster, slower, steep, less steep, gentle (a gentle slope), bumpy, smooth, and rough, as well as science process words such as observe, compare, same, different, change, and test.

Directions

Tell children they’ll go outside to explore the way a speciﬁc ball moves on inclines with different surfaces.

Have children locate different inclines outside—for example, a grassy hill, a paved driveway, a playground slide, a gravelly slope, or a sandy hill in the sandbox.
Have them experiment by rolling different balls down the inclines.
Take photos or videotape some of their explorations. Record their conversations, comments, and observations.

Reflect and Share

Encourage children to describe and compare the texture and the steepness of each surface. Record these on the “Different Surfaces and Objects” chart. Then have children indicate whether each incline was good for rolling or not. Ask:

Does the ball roll faster/farther when you send it down the grassy hill or the concrete ramp?
What do you think is different (about the concrete ramp) that makes the ball roll faster?
Why do you think the different balls roll differently?

Extension

What happens if children change the surface the object moves on? Try placing plastic or cardboard on the grass or concrete hill. Put a cardboard tube on a sandy hill. Or place a towel on the slide. Invite children to mark the distance a ball travels on these surfaces and compare that to the distance it traveled before. Does the grass slow down all the balls the same way, or just some of them? How about the sand? Or the towel? Why do they think that is so?

Related Video

Building More Ramps

Stand Alone

Indoor

20 - 30 minutes

Educator Close-Up

We rolled balls down both our concrete walkway and the grass right next to the walkway. We had soccer balls, Wifﬂe balls, tennis balls. We wanted to compare how the balls rolled on the concrete and on the grass, and then ﬁgure out which ball went the farthest. Here are some of the observations the children made as we experimented:

The ball won’t roll, the grass is in the way.

The concrete is better.

The grass is taller, the concrete is ﬂatter.

The grass pushed the ball and it stopped. If the grass was shorter it would roll. We should cut it!

The soccer ball went farther because it’s bigger.

Later when we were in the playground, one of the children pointed out that our two slides have different surfaces—one is smooth and one is bumpy. We decided to send identical objects down the two slides. Aiden and Caleb used ping pong balls. We let the balls come to a natural stop and compared how far they rolled. Caleb announced, “The slide that has bumps—that ball went the shortest.” Zoe and Jack sent craft sticks down the slides. Zoe, who used the smooth slide, said, “Mine was faster because of the slide. Jack’s slide was too bumpy.”

—Kira, preschool educator