CHILLS AND THRILLS
Grades K-2

What happens when ice melts? In these activities, students explore melting, and devise ways of speeding up and slowing down the melting process.

Science is Elementary #103: Let's Explore Water
Reading Rainbow #1008: Summer

The students will:

• explain that water is ice in a changed form.
• describe what causes ice to melt.
• create and interpret data on a time line graph.

• 3 ice cubes for each pair of students
• cooler or freezer to keep ice frozen until it is used
• chart paper
• teacher made graph of time passage (should span 1 hour, marked off in 5 minute intervals)
• a collection of insulating materials, such as fabrics, baggies, tape, cotton, packaging materials, foil
• 4 different colors of sticky notes, one each for each pair of students
• 1 "Ice Cube Outline" activity sheet for each pair of students

How many ice cubes does the class need in order to do the experiment? Children calculate-if each pair needs 3, then how many total does the class need?
Hold up an ice cube and asks the class to tell what they know about ice. Write student responses on chart paper.
Display the teacher made time graph in front of the class. Give each pair of children 1 ice cube with which to explore ice melting. Also give each pair of students 1 "Ice Cube Outline" activity sheet, and 2 different color sticky notes. Have the pair of students write their names
on the 2 sticky notes.
As the ice melts, the students will compare the size of this cube with the outlines on the activity sheet. When the ice cube fits into the smaller cube outline, the students place their first sticky note on the class time graph. When the ice cube has melted completely, the students put their second sticky note on the graph. After all the ice cubes have melted, review the data and discuss the time graph.
After the exploration, have the children come back to the brainstorm chart to add to and modify their original statements about ice.

Tell the class that they will be watching a video program in which some other children are exploring ice. Have the children watch for the answers to the following questions: What makes ice melt? How do we know the ice has melted?

CUE tape Science is Elementary #103: Let's Explore Water to the segment where the teacher leads the children in and exploration of ice melting, about 7 minutes into the program, right after the rain puppet show.
Show the segment pausing frequently during the exploration to do a reality check. Ask the students to explain what the teacher is doing. STOP the tape after about 3 minutes of viewing, when the teacher says "Excellent, we know that for a fact." Ask: "What is a fact?"

Discuss the video segment: "What made the ice melt?" (Heat in the room and from the children's hands). "How do we know the ice has melted?" (Water on the desks, children's hands, and in the containers).
Tell the children they are now going to experiment with the speed with which ice melts. First, they are going to try to make the ice melt fast. Give each pair of students another sticky note. Have the children write their names on the sticky note. Have them plan with their partners how they will make their ice melt fast. Keep the large time line chart at the front of the classroom.
Again, give each pair of students an ice cube. Have them all start melting their ice cubes at the same time. Announce the time elapsed every minute. When each ice cube melts, the partners will stick on their third sticky note. When everyone's ice has melted, discuss the time line. Have the children explain their methods and how they made their ice melt quickly.
Next, ask the children to think of ways they could slow the melting process. Show them the materials available. Have them plan with their partner a strategy to keep the ice from melting. When they are ready, let them choose some materials and bring them to their work areas. Give each pair the fourth and last sticky note, a different color from the others, and again have them write their names on it. Pass out the ice cubes and let the children begin the activity. Again, call out the time elapsed each minute. Again, have the children post their sticky notes when their ice has melted.
When everyone has finished, discuss which materials worked best to keep the ice from melting. Finally, compare the different sets of data. Have the children reflect on the activities and the results, either verbally or in their science journals.

Ask the students, "Why does snow melt in the spring?" Discuss the fact that when the weather gets warmer, the heat from the sun causes the snow and ice to melt.
Depending on the snowfall in your area, there are various ways to relate these classroom activities to real-world experiences. If your school is in a snowy area, your class can perform similar experiments with snow, varying sun and shade, etc. If you live in a non-snowy location, the children can experiment with ice in their freezers at home, melting it in different rooms of the house or indoors and outdoors.

1. Ice painting: You will need 2 or 3 colors of powder tempera paint, paper, and an ice cube for each child. Each child sprinkles the powder paint on his/her paper, and then slides an ice cube around on top of the powder. As the ice melts, the water will mix with the powder to make paint, creating designs on the paper.

2. Ice candles: This is a wonderful activity to show chemical changes. It seems more complicated than it actually is. The candles are beautiful, the activity is educational, and the children will remember the chemical changes they observe. Each child will need a small milk carton, and a popsicle stick. The class will need household wax (about 7 blocks for 32 students), crayon fragments, masking tape, a ball of string, a bag of small ice cubes, a hot plate, and pot with a spout. This activity requires an adult melting and pouring the wax, and works best if only 3-4 children go over to the heating area at a time.
Preparation: Write names on the milk cartons with permanent markers. Make wicks by dipping the string into melted wax and letting it cool. Cut the string into pieces, about 6 inches per candle. Tape one wick inside each milk carton, in the center at the bottom. Lay the popsicle stick over the top of the milk carton and gently wrap the wick around it. The wick should stay as straight up and down as possible. Melt the wax and color it by adding small amounts of crayon fragments.
The children fill their milk cartons about 2/3 of the way with ice. The adult then pours the wax into the cartons, making sure to cover all the ice. The children can watch the wax harden as it cools. The ice also melts as the wax heats it.
The next day, the children can peel off the milk cartons over the sink. Water will pour out of the holes in the candles, created by the ice cubes. The children can put their candles on paper plates, with their names on the plates. They can decorate the sides of their candles with glue and glitter. These make great gifts for parents, for winter holidays, Valentine's Day, Mother's Day, etc.

3. Ice Cream-Making: For each student, you will need: two resealable bags, one sandwich size and the other one gallon, 1 cup whole milk, 2 tbsp. sugar, 1/2 tsp. vanilla, 6 tbsp. salt, 2 cups ice, and a spoon.
Put the milk, sugar, and vanilla into the small bag and seal it. Add the ice and salt to the large bag. Place the small bag into the larger one, making sure the milk is surrounded by ice. Seal the large bag. Gently shake and squeeze the bags until the mixture is frozen (about 15 minutes). The children can eat their ice cream directly out of the small bag.

INTERNET EXTENSIONS

1. Students can compare their winter weather with other regions of the country either through pen pals or email. Students can decide on regions of interest after viewing the video, Reading Rainbow: Summer. Show the segment in which children from all over the United States describe their local winter weather and activities (13 minutes into the program). Continue into the spring segment, stopping the video when the music ends and the host, LeVar Burton, starts talking (about 5 minutes total).

2. A postcard exchange is a very popular internet activity. One such collaboration, "Postcard Geography," is easily accessible through America OnLine's Electronic School house. Many schools use this activity as a K-5 school-wide project, complete with maps, postcard displays, and printouts of email correspondences.
Postcard Geography
(America OnLine)
(To skip steps 1, 2, 3 & 4, use the keyword: esh to go directly to "The Electronic Schoolhouse.")
1. MAIN MENU

2. From Main Menu choose EDUCATION.

3. Within "Forums Listed Alphabetically" select TEACHERS' NETWORK.

4. Click on icon of THE ELECTRONIC SCHOOLHOUSE.

5. Within "The Electronic Schoolhouse" directly, select SCHOOL TO SCHOOL: PROJECTS.

6. Scroll down and select Postcard Geography.

Postcard Exchange is also accessible directly on the Internet by contacting:
http://town.pvt.k12.ca.us/Netscape2/start.html
Leni Donlan
Town School for Boys
2750 Jackson Street
San Francisco, CA 94115

Master Teachers: Meg Hudson, Sarah L. Hudson, and Linda Barnett