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Material Magic    Mystery 3

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Students learn about melting and the solid & liquid states of matter, then discover why plastic was invented. In the activity, students test the “meltable” property of candy.

Why are so many toys made out of plastic?

Beginning Exploration (1 of 8)
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Beginning Exploration (2 of 8)

Discuss:

Say you wanted to make a bunch of lion-shaped popsicles.

How do you think popsicle companies make lots of copies, without having to carve each one?

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Beginning Exploration (3 of 8)
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Beginning Exploration (4 of 8)

Discuss:

Why do you think toy companies started using plastic instead of wood? What do you think might be so special about plastic?

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Beginning Exploration (5 of 8)
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Beginning Exploration (6 of 8)

Discuss: (1/2)

Can you think of any other materials with this property? What else melts besides ice, plastic, metal, and glass?

For a hint, go to the next slide...

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Beginning Exploration (7 of 8)

Hint:

Is there anything you eat that melts?

Here is what we thought of...

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Beginning Exploration (8 of 8)

Discuss: (2/2)

Some candy melts. How can you test different kinds of candy to find out which kinds melt and which kinds don’t?

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Beginning Activity: Candy Melt
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Activity Prep

Step 1: Get supplies and print worksheets.

For each student, you will need:

For each pair of students, you will need:

  • a container with a lid (We use plastic food storage containers like these or these. You may be able to get some at your local deli.)
  • a styrofoam plate
  • a dozen chocolate chips or a square of milk chocolate

You’ll also need:

  • a source of hot water
  • a small bag of candy with a high melting point, such as jelly beans, gumdrops, OR Swedish fish
  • a small bag of candy with a low melting point, such as gummy bears (our favorite), Life Savers Gummies, OR gummy worms. Look for gelatin in the ingredient list.
  • a small bag of candy with an intermediate melting point, such as Starburst, caramels, OR butterscotch chips
  • (Optional — see below) a cooler (or a cardboard box and a bath towel)

Step 2: Prepare before class.

You need to fill baggies with candy for your students before class. (Once you have the supplies, this will take about 20 minutes.) Here’s what you do.

  1. Count out one baggie per student.
  2. In half those bags, put 12 chocolate chips or a small square of chocolate.
  3. Divide the remaining bags into three groups. Put high melting point candy in one group, low melting point candy in the second group, and intermediate melting point candy in the third group.
  4. When you hand out the bags to your students, make sure that each pair of students gets a bag of chocolate and a bag of some other candy.

Your students will melt their candy in containers of hot water. You need one container of hot water for each pair of students. When students do the activity, the water needs to be hot to the touch — a little above body temperature.

If you want to fill containers with water up to 3 hours before you do the activity, here are some tips:

  1. Start with water that’s hot enough to make a cup of tea (about 180° F or 82°C).
  2. Put the containers in a cooler (or line a cardboard box with 2 thick bath towels and wrap the containers up to keep them warm).
Beginning Activity: Candy Melt
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Beginning Activity: Candy Melt
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Beginning Activity: Candy Melt
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Beginning Activity: Candy Melt
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Beginning Activity: Candy Melt
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Beginning Activity: Candy Melt
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Beginning Activity: Candy Melt
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Beginning Activity: Candy Melt
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Beginning Activity: Candy Melt
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Beginning Activity: Candy Melt
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Beginning Complete!

You've completed the Exploration & Activity!

If you have more time, view the assessment, reading and extension activity in the optional extras.

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Optional Extras

Below are ideas for extending this topic beyond the activity & exploration which you just completed.

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Readings

These readings are free with registration on ReadWorks, a nonprofit committed to providing teachers with research-proven, Common-Core-aligned readings. All readings include comprehension questions.

  • Colorful Crayonstells how crayons are made, starting with melted wax.
  • Breakfast Timedescribes how some breakfast foods change when they’re heated.
  • A Camping Tripdescribes how marshmallows change when they are roasted over a fire.
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Picture discussion: The Big Stretch

How did this glass bottle get so stretched? Watch the glass video on the next slide for a clue.
stretchbottle

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Videos

Metal and glass are meltable. But to turn these materials from solid to liquid, you have to get them really really hot.

  • Glass melts 1: With a hot flame, this glass blower makes a glass tube soft enough to stretch.
  • Glass melts 2: A skilled glass worker shapes a horse out of hot glass.
  • Metal melts: Aluminum melts to make a shiny liquid that you can pour.
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Online Simulation

Exploring the properties of materials with simulations doesn't substitute for hands-on experiments, but it can help reinforce & expand students' knowledge.

An online simulation from the BBC lets students experiment by melting butter, candle wax, and other materials.

This is most appropriate for students who understand the concept of temperature, realizing that a higher temperature means that something is hotter. Students can observe that different materials melt at different temperatures. (They have different melting points).

Just like the materials in the simulation, the candies that students tested have different melting points.

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Image & Video Credits

Mystery Science respects the intellectual property rights of the owners of visual assets. We make every effort to use images and videos under appropriate licenses from the owner or by reaching out to the owner to get explicit permission. If you are the owner of a visual and believe we are using it without permission, please contact us—we will reply promptly and make things right.

Exploration
doll by Gabby , used under CC BY
legos by Priwo , used under CC BY
superman toy by JD Hancock , used under CC BY
toy car by Emi Yañez , used under CC BY
blocks by Josh Wedin , used under CC BY
horse by Garrison Gunter , used under CC BY-SA
wood car by Collectie Stichting Nationaal Museum van Wereldculturen , used under CC BY-SA
carving video by Gene Messer , used under CC BY
wooden lion by Ostheimer Toys , used under CC BY
zoo pops by World Wonders , used under CC BY
ice cubes by Liz West , used under CC BY
Ice cube melting by HeyHondo , used under CC BY
holding ice by AppleSister , used under CC BY-SA
wood by Elke Wetzig , used under CC BY-SA
Edmund Parkes by Barraud , used under CC BY
flask by Databese Center for Life Science , used under CC BY
army man by davidd , used under CC BY
lego man by sprout_labs , used under CC BY
Activity
mailbox by CGP Grey , used under CC BY
sign by Richard Leonard , used under CC BY
truck driving by Per , used under CC BY-SA
melting chocolate bar by Shizhao , used under CC BY-SA
caramel by Rainer Zenz , used under CC BY-SA
gummy bears by David O'Hare , used under CC BY