Effective Science Education involves Addressing Misconceptions
Engagement is one of the key indicators for any educator that effective learning is taking place. But how do we engage our students in learning and how do we know that they are actually learning?
Derek Muller, a popular science video blogger known for his YouTube channel, Veritasium, spoke about his thesis on “Designing Effective Multimedia for Physics Education” in a Ted Talk. He deduced that the amount of mental effort and work a student expended was positively correlated with how much the student learnt. He found that beginning the learning progress with demonstrating a common misconception with a concept (which is likely to be confusing) resulted in more effective learning than a clear and concise explanation of the same concept. I found it very relevant for the modern day classroom. A trap that occurs for me is wanting to provide a perfect explanation of a concept as opposed to guiding students through their own understanding and have them arrive at a clear understanding on their own.
There is a framework called the 5E’s teaching and learning cycle which is used in Science classrooms and it is based on the idea of inquiry-based learning. It is brilliant as it is supportive for learning and has a clear progression for increased cognitive complexity. It is also similar Bloom’s Taxonomy, which is used a common language for teacher’s to create learning objectives. The 5E’s are: Engage, Explore, Explain, Elaborate and Evaluate. Muller’s idea of addressing misconceptions immediately sits neatly in the first stage (Engage), where a student’s prior knowledge is accessed and questions are raised about the new concept.
Last week, my Year 10 Science students were surfing the net to conduct research into whether heavier balls fall faster than light balls. Of course, almost all students originally said “Yes, the heavier ball will fall faster”. It agrees with their day to day observations of life. The more they researched the more questions came up. “Surely an object with greater mass will have a greater force pulling it towards the ground. Does that mean it will accelerate faster?”. When student’s conducted the experiment there were varied results, but students slowly saw that the heavy ball (tennis ball) and the light ball (ping pong ball) had similar falling rates. But WHY?
There were only 2 forces acting on the falling object: gravitational force/weight (down) and air resistance (up). We generally don’t consider air resistance as it is very very small and doesn’t affect our numbers. So all we are dealing with is gravitational force. This takes us to Newton’s 2nd Law (F = ma). Rearranging this equation we have, a = F/m. As we can see, both gravitational force/weight (F) and acceleration (a) depend on mass. It turns out that heavier objects have a greater gravitational force and proportionally lower acceleration whilst lighter objects have a lower gravitational force and a proportionally higher acceleration. Hence, the only factor that affects the falling object is gravity. All objects on earth are falling at the same rate. A Wired article explains this concept very well, with equations and all!
Needless to say, the students went on a wild journey that lesson. I myself saw the necessity of first drawing out student’s initial understandings and ideas about falling objects. It made the learning meaningful and engaging.
