Liberty Bell students launch hot air balloons in STEM lab

Strong winds sent Liberty Bell students' handmade hot air balloons soaring across campus Thursday morning. The students learned about convection through the hands-on science lesson following weeks of testing preparation and TCAPS. Sixth grade teacher Kelli Pratt said the activity gives both students and teachers a break before the end of the school year while still reinforcing STEM concepts. "It's a really good hands-on STEM activity for the students after TCAPS," Pratt said. "It gets them away from the computers. It's a collaborative project. They are able to design the balloon themselves, they choose the pattern and they build the entire thing." Pratt said the school has been doing the project for about seven years after she and another teacher visited STEM-certified schools in the Nashville area alongside two East Tennessee State University professors. "On the day of our visit, we were watching the balloons," Pratt said. "We asked about the project, and they shared the instructions and some templates. We have been doing it ever since." Pratt said the hot air balloons are built using simple, everyday materials. "The balloons are constructed out of gift tissue and glue sticks," Pratt said. "Essentially, they glue five sheets of tissue together, and they do that seven times to create seven gores, which is what we call them. Once they have seven gores made, then they glue those gores together, and the balloon starts to come together at that point." "The bottom of the balloon is made out of newspaper that the students staple together into a ring, and the top we tie with ribbon," she added. "So it's just gift tissue, glue sticks, a piece of ribbon and newspaper." Teachers used a propane tank to fill the student-made balloons with hot air before launch. About the size of a large pillowcase, teachers said the balloons were part of a broader science lesson about convection and weather. "The hot air balloon relates to our convection lesson in our weather unit," Pratt said. "The students talk about warm air rising and cool air sinking and that continuous cycle. With the hot air balloon, they're able to see that warm air expands the balloon, and as it expands, the balloon rises. Eventually, the air inside the balloon begins to cool down, and when it cools down, then it begins to sink, which is exactly convection." Pratt said students eagerly anticipated working on the project each day. "They love it, so every day they come in asking, 'Are we working on our hot air balloons today?'" Pratt said. "They're also really excited to launch with their friends who were on other teams and to see how their balloons compare to their own." Students also turned the launches into a friendly competition, trying to see whose balloon could travel the farthest. Pratt said memorable launches from previous years motivate students to improve their designs each year. After the launches, students complete reflection exercises focused on critical thinking and problem solving. "One of the follow-ups that we do from the balloon activity, once we get inside, is asking what their thoughts were," Pratt said. "How did their balloons do? What could they have done to make their balloon better? Is there a material that you think could have worked better than gift tissue? — just to have that higher-order thinking piece and that reflection with the project." Students worked in teams to create balloons in a variety of colors and patterns, carefully patching holes and handling the delicate material throughout the process. Beyond learning about convection, students said the project also taught them the importance of collaboration. When asked about her favorite part of the project, student Kenleigh Ciralsky said, "just building with my friends and helping others." When asked what lesson she learned from the experience, Ciralsky said, "You need patience with other people." Student Tate Wassinger added, "Teamwork is easier than just doing it by yourself."