PBL Insights

Driving Questions Driving Students


The Challenge

In the infant stages of the second campus of MC2- Making Community Connections Charter School, 20 students discovered how easy it was to drive their own learning - and how challenging that learning could be. Originally, they signed up for a class called The Mathematician’s War, an interdisciplinary math/physics class with a layer of military history thrown in. A few weeks in, however, a unique challenge presented itself. The local Pumpkin Festival was hosting its first ever Pumpkin Catapult Competition and students wanted in.

The Idea

Building a functioning catapult in 3 weeks would prove to be a daunting task for a normal class, but this class was anything but normal. In the early brainstorming stages a lone voice insisted they should strive for an unprecedented design: the underhanded catapult. This idea proved controversial with students asking:

  • “Were there even any examples of underhanded catapults?” 
  • “Could an underhanded design fire?” 
  • “What forces are at play?” 
  • and most importantly (to the students) “How would an underhand launch compare to overhand counterparts?” 

The debate provided a rich field of questions that originated from the students, all they needed was a driving question to give it life. They settled on, “Why not build an underhanded catapult? Why might an underhand design take home the prize?”

The Strategy

Successful, responsive instruction requires teachers not to micro-manage content, but rather, to help shape the terrain for rigorous learning. Students broke down their driving question into a series of guiding questions with aligned tasks during their many design sessions. Working through the design process, students tackled: 

  • How do launch speed and angle impact trajectory?  Before the students could hijack the class, they had to make a compelling argument for how the catapult challenge would allow them to demonstrate the competencies targeted in the class. A brief investigation into how vectors and kinematic forces gave students enough background to make an informed decision to follow through with the new project. As the project grew the physics and math became “just in time” rather than “just in case” learning
  • How would an underhand launch work? This question had to be addressed before the group could proceed any further. As a divided class, it was decided that some students would tackle the prototyping of an underhanded design, using mostly rubber bands, glue and popsicle sticks. Their initiative proved successful; a 5” catapult consistently yielded a 15-20 foot range of results. The prototype was so compelling that the class unanimously voted to proceed with the underhand design after its introduction.
  • What physical forces influence the launch? These questions emerged as the challenge of scaling up a prototype developed. Using 2x4s and lag bolts was markedly different from popsicle sticks and glue. Most importantly the previously ignored forces of tension and torsion provided a challenge that stymied the class for almost a third of their design time. Students explored multiple materials in numerous configurations in order to design an effective launch. 
  • Why are there no examples of underhanded catapults in history (or on YouTube)?  Students were constantly asking this question, desperate for inspiration and tips on how to improve their design. The lack of examples was unhelpful but also compelling. Students were motivated to create a truly unique product and many even followed up after the festival looking at the historical factors contributing to this question. 

Additionally, as an actual building challenge students were constantly wrestling with the question, “Why won’t it work this time?” testing their skills in problem solving, collaboration, material management, and critical thinking.

The Win

As dawn broke on the day of the launch, the field of competition had whittled down from 5 other teams to 1. The MC2 students prepared their catapult alongside the one other school left standing. After a broken axle, snapped bungee cords, liters of coffee and almost no sleep, the catapult, aptly nicknamed “The Underdog,” was ready a mere 5 minutes before the launch. Everyone hoped for a simple lob but were pleasantly surprised when the first launch went off without a hitch. Not only that, but as the throws progressed the range steadily increased. With only 3 throws to the contest, students became convinced that with more chances, they could steadily improve their performance. Though they lost the distance category by a few feet, The Underdog led in the remaining categories – an impressive win for a team and school a mere 3 months old. What powerful evidence of learning they created!

This led, naturally, to their next question, “Who wants to compete again next year?”

Don’t believe us? Check it out here!