Posted: Wednesday, January 15th, 2014
In science education, a “discrepant event” is an attention-grabbing experiment or demonstration that upsets the viewer’s preconceived notions about how the world works. The more dramatic, the better! Discrepant events are a lot like magic tricks, at least in the sense that they want to make us want to get to the bottom of what we saw happen.
This impulse reaction is hugely valuable for teachers, as it prompts their students to follow through on the natural inclination to approach the world with a scientific mindset: apply background knowledge, make a hypothesis, and see if the results of the demonstration can be reproduced when different variables are changed. The best part? Plenty of students will be intrinsically motivated to do all of the above on their own if they’re shown something cool enough. Check out four of our favorite discrepant events from Education.com’s Science Fair section below.
Why does the water balloon get sucked into the bottle? Kids will apply what they know about pressure, states of matter, and condensation to make educated guesses and figure it out.
This experiment periodically makes the rounds on the internet and often gets accused of being fraudulent! It’s very real, very cool, and because it makes little visual sense when kids (and many adults!) are first confronted with it, it enriches their intuition regarding important physical principles like center of mass and torque.
When a pan is heated to extreme temperatures, water droplets released into the pan demonstrate some cool behavior. But what’s going on? And what explains the mind-boggling fact that water droplets evaporate more quickly in a pan that isn’t as hot?
This one is totally bizarre. Smoke itself isn’t flammable, right? Then something else in the air must be…
These projects require adult supervision to ensure that everything goes smoothly. But don’t jump the gun, parents! Let your kid make a hypothesis before you explain what happened in each project.