Drops on Different Surfaces

How do water drops behave on different surfaces?

Materials

  • eyedroppers or pipettes
  • containers of water
  • pieces of wax paper
  • paper towels
  • chart labeled “What Absorbs Water?/What Doesn’t?”
  • other surfaces to test: piece of paper, cardboard, plastic tray, piece of cloth, sponge, metal pan, cotton balls

Key Science Concepts

  • Water behaves differently on different surfaces.
  • Some surfaces absorb water; some don’t.

Vocabulary

Introduce the words absorb, soak up, and surface. Demonstrate what they mean using a sponge.

Directions

Tell children that they will do more experiments with water drops.

  1. Pass out eyedroppers, containers of water, as well as a piece of wax paper and a paper towel.
  2. Have children make drops of water on the wax paper and the paper towel. What happens? After they’ve observed how the drops remained on the surface of the wax paper but were absorbed by the paper towel, introduce the word absorb. Ask children if they remember exploring another object earlier in the week that was good at absorbing things (a sponge).
  3. Record children’s observations on a chart labeled, “What Absorbs Water?/What Doesn’t?”
  4. Then have children experiment with the different surfaces or materials you’ve provided—cloth, metal pan, cardboard, etc. Before they begin testing, ask them to make predictions about whether the surface or material will absorb the water or not.

Reflect and Share

Talk with children about what they notice.

  • Why do you think some surfaces absorb the drops and others don’t?
  • What do you think is similar about the surfaces that absorb the water?

Ask them to predict what would happen if you put drops on the water smock they are wearing. Then ask for a volunteer to demonstrate. Ask:

  • Why do you think we’re wearing water smocks? When is it helpful that something doesn’t absorb water? Ask for examples (umbrella, rubber boots, raincoat).
  • When is it good when something absorbs water? Ask for examples (sponges to wipe up spills, earth to absorb water for plants to grow). 

Add any new ideas to the “Our Ideas About Water” chart. Tell children that you will set up a Water Drop center next week where they can experiment more with drops.