This lesson is based on the PBS Design Kids Balloon Joust lesson.
Safety concerns and precautions: BBQ skewers flying through the air on a balloon sounds really dangerous, but if you have students wear the appropriate impact safety goggles and emphasize the need for safety, you should not have any issues. The balloons barely have enough force to propel the skewers forward, so we aren't talking about projectiles flying through the air at dangerous velocities. That being said, this could be dangerous if kids are too close, so make sure that everyone is paying attention during the battles to prevent injuries. Also, emphasize that the skewers are relatively sharp, so discuss this potential danger with students. If you have concerns that your cohort of students cannot handle safely participating in this lesson then you should not implement it.
Students develop the best jouster by determining the best placement for the BBQ skewer. Balloons are inflated and released so that the force from the escaping air propels the balloons towards each other. The goal is to pop the opponent's balloon before they pop your balloon.
During the process of designing the best solution, students develop Science and Engineering Practices, including Asking Questions and Defining Problems, Constructing Explanations and Designing Solutions, and Engaging in Argument from Evidence. Additionally, they will find patterns (CCC) when they analyze all their results to see if there are certain designs that are better than others, driving the iterative design process.
Prior to giving students materials and setting them free to build, it is important to explain the purpose of the activity and ensure that everyone has a voice. Since each student will have a opinion about the best location for the skewer, teachers must provide an opportunity for ideas to be heard, while managing time wisely. This means that strategies must be used that ask students to make predictions and evaluate the outcomes of each jousting trial.
Predict, Explain, Observe, Explain (P.E.O.E) is a strategy that is frequently used in my class, because it enables each student to record their predictions and explain why they think that. Based on the time consuming nature of balloon jousting, not everyone will get a chance to test their design ideas, but they will have an opportunity to predict the outcome of other students' design. The bottom line is that learning about trial and error, iterative design processes that are grounded in evidence acquisition and growth is the point of any engineering process. Therefore, assessment of learning shall not be placed on the success of the jouster, but the reflection of the outcomes and how those reflections are influenced by valid data.
Giving students the opportunity to test their ideas is an important first step in the process. I ask students to work on their own for several minutes to develop possible solutions to the jousting problem. They then share their ideas with their partners and come to a consensus about the best design to use in their first joust.
Students get a balloon, piece of drinking straw about 6 cm long, and 2 pieces of tape that are each approximately 4 cm in length. They then follow their blue print to build their design and predict what will happen during their first battle.
They then fill in the observation and explanation portion of the P.E.O.E. prior to testing their jouster. This is a good time for students to demonstrate that they have completed the required writing portion prior to battling. You should circulate around the room being sure that everyone in the group has thoroughly filled in their P.E.O.E..
A battle bracket is developed -- similar to the NCAA basketball tournament -- that has students battle each other to determine a winner. Students create a P.E.O.E. for each battle to drive the reflection process and help make connections to Crosscutting Concepts (structure and function). In that, students predict the outcome of the test and must justify their reasoning (I think ... because...).
After each battle, the students complete the observe and explain section of the P.E.O.E. In the end, students will have a log of P.E.O.E.s that helps them determine the best designs because it shows patterns and the relationship between structure and function. Students use this information to inspire the redesigning of their own jousters, in hopes of creating more effective jousters. This is where the rigor of the lesson lies, so make sure that they do this work (not you), and that they don't skip it in order to rush into a redesign and renewed battle. This might require that you stop all activity occasionally and ask students to remind themselves and each other, what process must we do each time?
* There are online bracket templates that can be used rather than drawing your own.