Materials Needed

• Glacier Gloop: 1/2 cup white school glue, 1/2 cup water, 1/4 cup liquid starch (or contact lens solution + baking soda), and blue food coloring.
• The Landscape: A large plastic tray or cookie sheet.
• Earth Materials: A handful of sand, small pebbles, and a dusting of flour or cornstarch.
• Tools: A stack of books (to create a ramp), a stopwatch, and a ruler.
• Visuals: Photos of real glaciers (U-shaped valleys, crevasses).

Learning Objectives

By the end of this lesson, Natalie will be able to:

• Define a glacier as a "moving river of ice."
• Explain how gravity and weight cause glaciers to move.
• Identify two ways glaciers change the land: erosion (carving out) and deposition (leaving things behind).

1. Introduction: The Slow-Motion Bulldozer (10 Minutes)

The Hook: Ask Natalie: "If you left a giant ice cube on the sidewalk, what would happen? It would melt, right? But what if that ice cube was the size of a skyscraper and lived in a place so cold it never fully melted? It wouldn't just sit there—it would start to crawl!"

The Concept: Explain that glaciers are like giant, heavy, frozen rivers. They are so heavy that they actually flow downhill, very slowly. They are nature’s greatest sculptors—they can turn a flat field into a deep valley or crush rocks into tiny sand.

2. Body: I Do, We Do, You Do (40 Minutes)

I Do: The Science of "Squish"

Demonstrate how snow becomes ice. Use a piece of bread or a marshmallow. Press down on it with your palm as hard as you can. Show how the air is pushed out and it becomes dense and hard. Explain that in a glacier, hundreds of years of snow pile up and "squish" the bottom layers into solid blue ice.

We Do: Creating the "Glacier Gloop"

Together, mix the glue, water, and liquid starch/borax solution. Add blue food coloring.
Why? Real glacier ice isn't like an ice cube from the freezer; it behaves more like a very thick, slow-moving liquid (scientists call this "plastic flow").

• Propped up one end of the tray with books to make a hill.
• Dust the tray with flour (representing soil) and sprinkle pebbles and sand (representing rocks).
• Place the "glacier" at the top of the hill.

You Do: The Great Glacier Race & Carve

Natalie takes the lead as the scientist:

1. Predict: Ask her, "What will happen to the rocks and flour when the gloop moves?"
2. Observe: Use the stopwatch to see how long it takes for the glacier to reach the bottom.
3. Analyze: Look at the "path" left behind.
   • Erosion: Did the glacier pick up the pebbles? (This is called "plucking").
   • Deposition: What happened to the pebbles when the glacier stopped? (This is called "moraine").
   • Scratches: Look at the flour. Did the pebbles make "striations" (scratches) in the "ground"?

3. Conclusion: The Big Freeze Recap (10 Minutes)

Summary: Recap the three big ideas:

1. Glaciers move because they are heavy and gravity pulls them down.
2. They act like sandpaper, scratching the earth (Erosion).
3. They act like delivery trucks, dropping rocks far from where they started (Deposition).

Discussion: Ask Natalie: "If a glacier melted tomorrow in your backyard, how would we know it was ever there?" (Answer: Look for giant rocks it left behind or deep U-shaped holes in the ground!)

Success Criteria

• Natalie can explain that glaciers move downhill using the word "gravity."
• Natalie can point to the "path" in her tray and explain how the glacier changed the land.
• Natalie can identify the difference between "picking up rocks" (erosion) and "dropping them off" (deposition).

Adaptability & Differentiation

• For More Challenge: Research "Ice Ages" and look at a map to see which parts of the world were once covered by glaciers. Use the ruler to calculate the "speed" of the gloop (Distance divided by Time).
• For Extra Support: Focus purely on the sensory aspect of the gloop and the visual of the "scratches" left in the flour. Use a video clip of a glacier "calving" (breaking off into the ocean) to show their power.
• Multi-Sensory: If it's winter, go outside and try to compress snow into "glacier ice" with your boots!

Assessment

Formative: During the activity, ask: "Why isn't the glacier moving fast like a waterfall?" or "What is happening to that pebble as the gloop rolls over it?"

Summative: Have Natalie draw a "Before and After" picture of a mountain landscape. The "Before" should show a sharp V-shaped valley; the "After" should show a wide U-shaped valley with a glacier and some "dropped" rocks at the end.