7.3 POLAR SURVIVAL

Why Do Mittens Keep Our Hands Warm?Activity Time: 30 minutes

1. Bring a box of summer and winter clothes/accessories. Mix them up in a box or container. 2. Ask for volunteers and have them find an item of appropriate clothing for summer and winter. Ask the

rest of the class to make claims as to why they chose these particular clothes. 3. Ask students what kind of clothes people wear in Antarctica? 4. Ask “How do clothes keep you warm?”

1. Divide the class into groups and provide one pair of mittens for each group. 2. Have students pass around the mitten and have them write down how it feels before and after they put it

on. Have them write down observations in their journals. (Texture, temperature, color, material)3. Introduce the concept of a thermometer and how to read it. 4. Give each group two thermometers. Have them read the temperature on it. Have them write down this

temperature as the “room temperature.” 5. Have the class guess as to whether the temperature inside the mitten will be warmer than the

room, colder than the room, or the same temperature as the room. Introduce and define the word “hypothesis” and have them write down their hypothesis in their observation journals.

6. Have students place one thermometer in the mitten. After 3 minutes, record the temperature.

1 pair of mittens for each group2 thermometers for each groupObservation journalsPencilSummer and winter clothes/ accessories

Background MaterialsIn the Polar Regions, it is imperative to wear mittens to keep the fingers and hands warm. Prolonged exposure to cold temperatures here causes frostbite quickly, especially the head, face, ears, hands, and feet because they are farther away from the body’s core. When temperatures feel like -19 degrees Fahrenheit, frostbite can occur in 30 minutes. However, in Antarctica where researchers sometimes work in temperatures below -70 degrees Fahrenheit, frostbite can occur in minutes and even leave permanent damage on their lungs from just breathing in the cold air. In order to avoid frost bite, several layers of insulated clothing is needed. This lesson serves to introduce the concept of insulation and clarify the idea that clothing insulates energy but does not produce energy.

• Move all the students into three groups based on what they guessed. Have each group explain why they came to their conclusions

• Ask “what makes the mitten warm?” Write the ideas on the board and discuss.The mitten is not producing its own energy. The mitten is not warm by itself. Whoever wears the mitten is warm because a mitten simply serves as an insulator, which slows down the transfer of heat energy into the surrounding environment outside of the mitten. It keeps the warmth of your hand trapped inside, and that heat, your own heat, is what keeps you warm. If nothing is inside the mitten, there is nothing for it to insulate energy, and so it remains at the same temperature as the rest of the room.

Class Questions:• Does a mitten produce heat or keep heat trapped? Keep heat trapped• What word do you use for “keeping heat trapped?” Insulate.• Why can’t a mitten produce heat? Because it doesn’t produce its own energy.

Place a thermometer in the mitten with your hand for 3 minutes and record the temperature.

Discussion

Activity

Extension

VocabularyHeat: The transfer of one area of energy

to another and is felt as temperature.

Energy: How things change and move,

“the ability to do work.”

Temperature: The degree of hotness

or coldness using a thermometer.

Frostbite: Frozen body tissue that

can affect the skin, muscle, and even

bone, caused by prolonged exposure

to cold temperatures

Directions

ALIGNMENT TO NGSS:Scientific and Engineering Practices:

• Obtaining, Evaluating, and Communicating Information

• Analyzing and Interpreting Data• Planning and Carrying Out

InvestigationsCrosscutting Concepts:

• Structure and Function• Cause and Effect• Energy and Matter

Disciplinary Core Ideas: • K – 2: K-LS1-1.C, K-ESS3-2.

Assessment