Teachers should keep in mind that discovery and inquiry learning activities have a downside-one related to the confirmation bias phenomenon I mentioned in Chapter 10. In particular, students may misinterpret what they observe, either learning the wrong thing or confirming their existing misconceptions about the world (de Jong & van Joolingen,1998; Hammer, 1997; Schauble,1990). Consider the case of Barry, and eleventh grader whose physics class was studying the idea that an object’s mass and weight do not, in and of themselves, affect the speed at which the object falls. Students were asked to design and build an egg container that would keep an egg from breaking when dropped from a third-floor window. They were told that on the day of the egg drop, they would record the time it took for the gees to reach the ground. Convinced that heavier objects fall faster, Barry added several nails to his egg’s container. Yet when he dropped it, classmates timed its fall at 1.49 seconds, a time very similar to that for other students’ lighter containers. He and his teacher had the following discussion about the result;