Although Piaget developed specific tests for each stage, a child’s cognitive level may be diagnosed from everyday aspects of cognition as well. Below are a number of statements children might make at home or school. Indicate which of the following cases best illustrates formal operations. Choose the best answer, explain why it is the best answer, and explain why each of the other answers is not as appropriate.
Katie is asked, “Do you have a brother?” She says, “Yes.” Then she is asked, “Does he have a sister?” She answers, “No.”
Ray says, “A fly is like both insects and birds. It’s like birds because it flies, but it’s like insects because it has six legs.”
Tim is working on analogies. He declares, “Biking is to pedaling as riding in a car is to stepping on the gas pedal because they both make the vehicle go!”
Bobby states, “I understand how this nickel and these five pennies are the same as this dime.”
Her teacher asks Mary, “How can the scale be brought back into balance?” Mary replies, “The only way to do that is to remove the weight that made one pan sink lower than the other.”