All About Ice

Flubber Flows


Flubber Flows is a 30-minute activity in which teams of four to five children ages 8 to 13 experiment with Flubber and investigate how a solid can flow! They predict and model the properties of glaciers, view images of advancing glaciers, and create their own Flubber flow!

What's the Point?

  • Under the right conditions — under high pressure — ice, the solid form of water, flows.
  • In a valley glacier, friction between the ice and the walls and floor of the valley it is flowing down causes the base and edges to flow more slowly than the center.
  • Malleability (pliability) and viscosity (how much a liquid resists flowing) are properties of matter.


For each child:

For each group of three to four children:

  • A softball softball size blob of Flubber
    • Measuring cups
    • Measuring spoons
    • 2 mixing bowls
    • 1 cup of white glue
    • 5 drops of green or blue food coloring (optional)
    • 1 1/4 cup warm water
    • 2 teaspoons of Borax
  • 1 (20" x 30") or larger piece of foam core or heavy cardboard
  • 1 pint sized Ziploc baggie
  • 1 permanent marker
  • 1 pair of scissors
  • Ruler
  • Pencil or pen
  • Images of Amundsen Scott South Pole Station, Antarctica
  • Images of retreating glaciers
  • A timer, watch, or clock

For the facilitator:


Flubber Flows has three parts and can be done in a variety of ways. It can be facilitator-lead as a demonstration or can be set up as a team activity, or a combination of the two. The activity below is a combination of demonstration and hands-on experimentation.

  • Prepare the Flubber in advance. Multiply the ingredients by the number of teams participating. Flubber may be stored for several weeks in air-tight baggies. Simply rework some warm water into the Flubber to return it to the desired consistency. Flubber looks like taffy, but is toxic and should not be ingested. Young children should do this activity only under supervision.
    • Mix 3/4 cup warm water, 1 cup of white glue, and 5 drops of blue or green food coloring, and set aside.
    • Separately mix together 1/2 cup of warm water and 2 teaspoons of Borax
    • Combine the two mixtures and work it through your hands for several minutes until a consistent texture forms. Drain excess water, and
    • work into a ball. Note: Using gloves to work with the Flubber may make it more difficult. It really is not as sticky as you might think!
  • Place each ball of Flubber in a Ziploc baggie.
  • Prepare an area large enough for each team to work separately and for you to meet together as a larger group.


  • Make sure to keep track of the time as you are discussing the images of the glaciers. You should allow about 10–15 minutes for the discussion, which will allow the Flubber flows time to deform. Don't allow too much time, however, or an important part of the experiment may disappear!
  • You may wish to extend this activity for older children to include measuring and timing the flow of Flubber and or you may test variables such as temperature of the Flubber or angle or roughness of the board across which it flows.


1. Introduce the activity by revisiting the three states of matter with the children.

  • What are the three states of matter?Solid, liquid, and gas.
  • In what state of matter is ice? Solid.
  • Can a solid flow? Accept all answers for now.

2. Divide the children into teams of three to four and distribute the foam core boards, markers, scissors, pencils, rulers, and the baggies of Flubber to each team. Invite them to remove the Flubber and feel it. Have them roll it around in their hands.

  • Do they think Flubber is a solid? Why or why not? Accept all answers for now. In our experiences liquids change shape to fill the container holding them. Solids maintain their shape. Liquids tend to flow; solids tend to break.
  • What are some words they would use to describe Flubber? Is it hard or soft? Is it gummy, gooey, or sticky?

If they used words like mushy and gooey, share with them that these are words that describe Flubber's viscosity. Viscosity is the measure of a fluid's resistance to flow. The more viscous a substance the stiffer it is and the more that it will resist flowing.

  • Is their Flubber rigid or flexible? Flubber is very "malleable," meaning it is very pliable, or bendy.
  • Can they break the Flubber? Under stress — if the children pull hard enough and fast enough, the Flubber will break or fracture.

So far, we have determined that Flubber is very viscous (thick), and malleable (bendy), and it can break.

3. Give the children an opportunity to play with the Flubber, and ask them to predict whether Flubber can flow.

  • How might they make Flubber flow — or change shape — quickly? Slowly?

4. Invite the children to form their blobs of Flubber into 5 inch by 6 inch rectangles, and draw a line across the Flubber center with a marker. Share with the children that they are creating a model of a glacier.

  • What is a glacier made of? Ice.
  • Is ice a solid, liquid, or gas? Solid.
  • Does ice move? Does it flow? Answers will vary.

5. Invite the teams to carefully place their Flubber at the top center of their boards. Have them draw a line even with the bottom of their Flubber "glaciers," across the board.

6. Have each team prop up their boards— lengthways — against a wall, with the bottom of the board one foot from the wall. You may also wish to have the groups prop their boards at different angles.

  • What do they think will happen to the Flubber if they leave it on the board for awhile?
  • Will it change?
  • How quickly or slowly might it change?

7. Ask the teams to leave their Flubber experiments for now and move to an area where they can view the glacier images. Share the images of Antarctica's Amundsen Scott South Pole Station with them. Before telling them anything about the images, invite their observations.

  • What does the first picture show? The research base, Amundsen Scott South Pole Station. The different buildings include dormitories, research laboratories and offices, a library, a cafeteria, maintenance facilities, and more. The long wide strip between the groupings of buildings is an airstrip where planes land. Most people and materials arrive at the station by plane.
  • What is the ground made of that the station is built on? Ice! About 98% of Antarctica is covered by giant sheets of ice and glaciers.

    Have the children examine the next three images.
  • What do they show? Markers marking the geographic South Pole. The markers are stuck in the ice sheet.
  • What is the geographic South Pole? It marks the location where Earth's imaginary axis of spin or rotation intersects Earth's surface. Earth spins around this point.

    The geographic South Pole does not change position; it is always located in the same place. Yet every year, a new marker has to be put into place to mark the spot. This new marker is about 33 feet (10 meters) from the marker of the year before. Picture # 4 shows the markers from 1996, 1997, and 1998. The 2008 marker that is over the geographic south pole is about 330 feet (100 meters) away from the 1998 marker.
  • Why does a new marker have to be placed? If the geographic South Pole is always in the same place, and no one moves the poles away, what moves? The ice in which the markers are placed must move or flow.
    Ice is a solid. However, under pressure and over long periods of time, it flows. Glaciers and ice sheets slowly move. The movement of the ice sheet over the south geographic pole carries the markers away from the geographic South Pole.

    Invite them to examine picture # 5.

  • What does it show? A glacier that is flowing between mountains.

    How does a glacier or ice sheet form? Glaciers can form anywhere that snow falls and stays (accumulates). Enough snow must fall that it accumulates over time, and does not go away in the summer. Eventually the light snow flakes get compacted as they get buried under more and more snow — they become ice. As more and more ice accumulates, it eventually begins to flow. In the case of glaciers, they often flow down a mountain valley.

8. Predict! After viewing the images of the ice at Amundsen-Scott South Pole Station and the glacier in Alaska, ask the children what their predictions are now about the way in which their Flubber behaved while they were gone!

9. Invite the teams to return to their boards to view the Flubber flows!

  • What do they observe? How do their observations compare to their predictions?
  • What happened to the mark they made on their Flubber? The middle of the mark (and the middle of their Flubber flow) advanced a lot!
  • Did the edges of the Flubber advance from where they started to another location farther down the board?
  • How did it do that? The Flubber flowed.
  • How did the flubber flows at various angles, or slopes, differ from one another?

Ask the teams to measure how far their Flubber flow advanced and share their meashurements with the group.

10. Share the images of the retreating glaciers.

  • What do the pictures show? Glaciers.
  • Invite them to look at the two images of Qori Kalis Glacier in Peru. What do the two pictures show? The same glacier but in different years.
  • What do they observe about the glacier in this pair of images? The glacier is not growing or moving forward or advancing. Its edge or nose is retreating or appears to be going backwards.
  • How might this happen? Remind the childre how glaciers form and grow.
  • What do they think happens if a glacier stops getting snow, or gets less snow, or begins to melt faster than it gets snow? The glacier will shrink and its edge, or nose, will retreat.
Note to Facilitators:

Glaciers never go backwards! They always flow "forward" with gravity, regardless of if they are growing or getting smaller. When glaciers accumulate mass faster than they lose it through ablation (melting or sublimation of ice), they grow and their leading edge(s) advances. When they lose mass faster than they accumulate snow, their mass decreases and their leading edge(s) retreats.

Have the children view the other glaciers.

  • What do they observe is happening to the glaciers over time? They are all retreating or getting smaller.
  • What do the children predict will happen to these glaciers in another 10 years? Answers will vary.
  • Why might the glaciers all be getting smaller? Answers will vary. Some children may suggest that our temperatures are getting warmer.

11. Help the children make the connection between their Flubber flows and glaciers.

  • Does their Flubber flow resemble any of the photographs they viewed? Yes. It looks like the advancing glacier.
  • How is Flubber similar to ice? It is a solid. It flows very slowly.


If the children have started to construct a snow mobile, invite them to record any answers they discovered on the appropriate pieces. Some of the questions that they can answer might include:

  • Can solid ice flow?
  • Name one example of flowing ice

Have them annotate any new questions they have or interesting things they learned on the appropriate shapes of either raindrop, cloud, or snowflake.

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