Teaching convection of heat? Give kids get hands-on experiences. Start with simple experiments. Then discuss characteristics. In this form of energy transfer, warm air or water rises.
Ms. Sneed Prepares for Teaching Convection of Heat
Our favorite fourth grade teacher sat at the side table with her teaching partner. “Time to continue our thermal energy unit,” she said. “Today we taught conduction. Next up, convection.”
On cue, Mr. Frank opened his laptop. In no time, he found their heat materials.
“As in all of these other physical science activities, kids use an inquiry approach and make generalizations.” He turned his screen so she could see.
Ms. Sneed nodded. “Simple. Just the way I like it.”
Ms. Sneed Begins Teaching Convection
Before school the following morning, Ms. Sneed gathered the necessary materials. First, pulled out some plastic cups and straws. Second, she grabbed some yellow construction paper and scissors. Finally, she headed to the teachers’ lounge to microwave a pitcher of water and grab some ice cubes.
When she returned, Ms. Sneed poured water into six of the cups. Into each, she plopped several ice cubes. Then she added a few drops of blue food coloring and stirred.
Soon her students began to file in. As usual, they gathered around the table. “Hmm,” said one child, “I wonder what we’re doing in science this morning…”
Activity 1
Once she had taken attendance and lunch count, Ms. Sneed began teaching convection. “Today,” she said, “you’re going to learn about convection, another type of heat transfer. At the beginning of the lesson, you’ll work in your science lab groups.”
“Yay!” came the cheer. Obviously, they loved group work.
When the groups were arranged, Ms. Sneed handed out their lab sheets. Then she had the appointed students grab supplies:
“Group member one,” she called out, “come and pick up one of these cups of blue food coloring.” Quickly, one student from each group came and picked up the cup.
“Number two, take a straw and an empty cup.” Again, students gathered the materials.
“Now,” she said, “I’ll come to your group and pour hot water into the empty cup. When you’re ready, follow the directions on the sheet. As you see, you should use the straw to drop some of the cold, blue water into the hot water.”
After their teacher poured their hot water, each group got busy. “Hey!” came the calls, “The blue water is sinking!”
Activity 2
Once the students had finished the first hands-on experiment, Ms. Sneed got started on the second. “You just saw that cold water sinks. Or maybe warm water rises? In any case, my second part of teaching convection involves air.”
As she spoke, she distributed half a sheet of yellow construction paper to each student. “Next, you will make a curlicue. If you look at your lab sheet, it shows how. Just begin on the outer edge and keep cutting around in a circle. Then you can pick it up from the middle.”
Again, Ms. Sneed circulated around the room. Several times she provided assistance. And once she offered a new sheet of paper to someone whose cutting had gone awry.
Next, the teacher gave each student a straight pin. Then she demonstrated how to attach it to the curlicue. “Stick it into the top from the underside. Maybe give it a little twist to make sure that the curlicue can spin. You’ll hold it from the top.”
All around the room, kids were trying out their curlicues. As directed on their lab sheets, they wondered over to the radiator and held it over it. Unfortunately, nothing happened.
“Hmm,” said Ms. Sneed. “It looks like our radiator isn’t generating any heat right now. Last year, we also had trouble finding a heat source to use. Let’s take our curlicues home tonight and see what we can find. Never, however, should you hold it over a burning flame.”
The next day, Ms. Sneed continued teaching convection. “How did it go with the curlicues?” she asked.
Unfortunately, the results were mixed. Some kids were able to get theirs to spin, while others weren’t.
Fortunately, Ms. Sneed was prepared. From her closet, she pulled out a space heater. After turning it on high, she invited her students to try it out. Sure enough, the little curlicues began to spin.
“Hey!” shouted one kid. “Warm air rises!”
Defining Convection
Ms. Sneed giggled. “I guess it’s time to finish those lab sheets.”
At the bottom of the page, kids easily responded that warm air or water rises, and cool air or water sinks.
“So,” Ms. Sneed asked, “what is convection?”
A boy in the back called out. “It’s when warm air or water rises.”
“Right!” Ms. Sneed picked up a marker. “From our earlier discussions, you know that heat is energy. Therefore, the warm air and water provide the key.” As she spoke, she wrote a definition on the board:
Convection of heat occurs when thermal energy rises.“
Enjoy Teaching Convection
Later that afternoon, Ms. Sneed again sat at the side table with Mr. Frank. “Teaching convection was actually rather easy,” she said. “And yes, I enjoyed it. However, I feel like my job isn’t done. After all, we barely touched on its importance.”
“No worries,” her teaching partner responded. “These simple experiments introduced the concept. Later this year, we can reinforce the concept. For example, when we teach the Great Lakes, we can discuss how they layer in the winter and turn over in the spring.”
Ms. Sneed’s face brightened. “Then when we work on volcano mapping, we can even talk about underground convection. You’re right. This provided a great introduction. Additionally, it helps kids discriminate between different types of energy transfer.”
“Yep,” Mr. Frank replied. “Now it’s time to plan for teaching radiation.”
