No one ever said science education was easy. Certainly the concepts we teach, like conservation of momentum or quantum mechanics, can be hard to grasp. But what really complicates the endeavor is that we’re also trying to teach a deeper lesson at the same time—to help students understand the nature of science itself.
All too often, young people get the impression that science is about learning certain “laws” and then applying them to different situations. After all, that’s what we make them do on tests, to show that they’ve been doing the work. But that’s not it at all. Science is the process of building these concepts through the collection of experimental evidence.
And while I’m on it, let’s call these concepts what they really are—not laws, but models. Science is all about building and testing models. It’s difficult to help students understand that aspect of science when we just give them the models to begin with. Sure, in physics we often include historical or mathematical evidence to support big ideas, but that often isn’t enough.
Of course, we can’t start from scratch. If students had to build their own models from the ground up, it would be like trying to learn programming by inventing computers. As Isaac Newton is supposed to have said, we stand on the shoulders of giants. We must take models built by others and go from there.
But there’s still another challenge in science education that is less often recognized: Students often enter a course with their own unarticulated ideas about how the world works. We call these “misconceptions,” but it’s important to realize that these are also models, based on their life experiences, and that they must “make sense” to the student.
What I’d like to suggest is that this actually provides a great way into the adventure of science and an opportunity to meet our objectives as educators. If you can create a situation that challenges students’ assumptions and produces conceptual conflict, that’s a great opportunity for learning.
This Little Light of Mine
Here’s a fun example that I’ve used, on the topic of light rays. I set up a point light source and put a piece of cardboard in front of it. There’s a small pinhole in the cardboard and a white screen behind. What do you expect to see?
No surprise: A light shining through a pinhole makes a dot on the screen. Now I’ll ask the students: What if I have TWO light sources with the same single hole?