Explore and Play: Rough and Smooth Ramps

Materials

• Down They Go (video)
• a new chart, labeled “Different Surfaces and Objects” (see example below)
• baking pan or cardboard (for a smooth ramp)
• piece of corrugated cardboard, towel, or other material with a raised surface (for a roughly textured ramp)
• boxes, building blocks, and other objects for supporting the ramps
• paper clip and small ball

Vocabulary

Introduce the words surface, texture, rough, and smooth. Encourage children to repeat the words and to explain or offer examples of what they mean. 

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.

Directions

Tell children that the surface of the ramp can affect how something rolls or slides down it. Talk about what texture means: the way something feels when you touch it. Explain that some textures are good for sliding or rolling and others are not.

1. Show children the two different ramps: the baking pan and the corrugated cardboard. Ask them to feel the surfaces and describe what they feel like.
2. Ask children to predict whether they think a paper clip will slide more easily down the baking pan or the corrugated cardboard if they are the same slope. Then have a volunteer try it. Do the same with the ball. Then fill in the chart, describing what the surface is like, what the object is, and whether the object rolls or slides.
3. Watch Down They Go again, asking children to observe the surfaces of the ramps in the video and whether they are good for rolling, sliding, or not. Have them describe the surfaces, indicate whether they are steep or not as well as anything else they notice, and fill in the chart.

You’ll use this table several times during the curriculum. In other activities, you’ll also be adding objects with different textures that move down ramps.