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Grow Your Own Stalactites

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From: Aussie Childcare Network

Grow Your Own Stalactites

A stalactite is a type of mineral formation that hangs from the ceiling of caves. Watching the slow formation of stalactites teaches patience and keen observation skills. This science project provides hands-on learning about geological processes and the formation of stalactites and stalagmites. The following article provides information on What Is A Stalactite, The Experiment, and more. 

What Is A Stalactite?

A stalactite is a type of mineral formation that hangs from the ceiling of caves. These icicle-shaped deposits are formed by the accumulation of minerals, usually calcium carbonate, which is deposited by dripping water. Here’s how they form:

  1. Water Dripping: Water seeps through the ground and dissolves minerals from the rock, carrying them along.

  2. Drip by Drip: When the mineral-laden water drips from the ceiling of a cave, it leaves behind tiny deposits of minerals.

  3. Growth Over Time: Over many years, these minerals build up to form stalactites hanging from the ceiling.

Interestingly, stalactites are often found alongside stalagmites, which are similar mineral formations that grow upward from the cave floor due to dripping water.

The mnemonic to remember: stalactites hang tight from the ceiling, while stalagmites might reach the ceiling from the ground.

The Experiment

Materials Required

  • Two mason jars

  • Baking soda (or Epsom salt)

  • Hot water

  • A piece of string

  • A small weight (like a paperclip)

  • A shallow dish

What To Do

  • Prepare the Solution: Fill each mason jar with hot water. Dissolve as much baking soda (or Epsom salt) as you can into each jar by stirring thoroughly.

  • Setup: Place the jars about 6-8 inches apart. Attach a small weight (like a paperclip) to the middle of the string to ensure it dips into the dish placed between the jars.

  • Connect the Jars: Drape the string between the jars, ensuring that each end of the string is submerged in the solution in the jars. The middle section of the string should hang down and touch the dish.

  • Observe: Over several days, you'll notice water traveling along the string and dripping into the dish. As the water evaporates, it will leave behind baking soda crystals, forming stalactites on the string and stalagmites in the dish.

Hints and Tips

  • Patience is key! This process may take a week or more.

  • Ensure the jars stay in a place where they won't be disturbed.

  • If you want to speed things up, you can periodically add more baking soda solution to the jars.

Reference:
Howwelearn.com

Additional Info

  • Appropriate Age: 3 year+
  • Number of Children: Individual (1)
  • Developmental Milestones:

    • Ages 3–4: Beginning to understand cause and effect (“If I add salt, something changes”).

    • Ages 4–5: Can make predictions and test ideas (“I think crystals will grow faster on this string”).

    • Ages 5–6: Able to compare outcomes and notice patterns (“This side grew more because…”).
  • Play Based Learning: Exploratory Play
  • Interest Areas: Science and Nature
  • Games Categories: Science Experiments
  • EYLF Outcomes: Learning Outcome 1, Learning Outcome 2, Learning Outcome 3, Learning Outcome 4, Learning Outcome 5
  • Sub Outcomes:

    • Outcome 1: Children have a strong sense of identity

      • Children feel confident as “scientists” exploring cause and effect.

      • They take ownership of their experiment setup, building pride in their contribution.

    • Outcome 2: Children are connected with and contribute to their world

      • They learn about natural formations (stalactites/stalagmites) and connect this to caves and the environment.

      • Builds awareness of geology and how water shapes landscapes.

    • Outcome 3: Children have a strong sense of wellbeing

      • Promotes patience and persistence as they wait for crystals to grow.

      • Encourages safe handling of materials and following instructions.

    • Outcome 4: Children are confident and involved learners

      • Experimenting with salt solutions fosters curiosity, problem-solving, and prediction skills.

      • They observe changes over time, strengthening scientific thinking.

    • Outcome 5: Children are effective communicators

      • Children describe what they see, compare results, and share ideas with peers.

      • They may record observations through drawings, photos, or simple charts.

Printed from AussieChildcareNetwork.com.au