What Is Learning and How Does It Occur? 5
The constructivist approach to learning had one point of origin in the work
of Piaget and his followers and another in the information processing para-
digm that came to be prominent in cognitive science. There are now many
different forms of constructivism, but each of them embraces several basic
tenets. First, knowledge cannot be transmitted from one individual to an-
other individual in any mode. Knowledge is built by the learner using inter-
nal cognitive processes acting on stimuli from the environment. The result
is a mental representation, or model, of the "real world" that can be used to
solve problems. These representations or models may be well defined or
they may be ill defined. In any event, as the learner continues to learn, they
will be modified and refined.
Of course, this means that it is the learner who is responsible for the learn-
ing that occurs. It also means that all we, as teachers, can do is to help the
learner to learn. Second, the learner's process of building new knowledge
starts with a foundation of everything that is already known by the learner.
The learner is not simply a blank slate (tabula rasa) on which experience
writes the new lessons being learned (Bransford, Brown, & Cocking, 1999).
It is clear, however, that at least some of what the learner already "knows"
is wrong in whole or in part. This "wrong" knowledge has been labeled by
investigators as misconceptions, alternative conceptions, and naive theories
(Wandersee, Mintzes, & Novak, 1994). Whatever labels are used, they de-
scribe some kind of conceptual difficulty that the student is having (Michael
et al., 2002). We will use the term misconceptions to refer to such "incor-
rect" knowledge. The significance of misconceptions is that their presence
inevitably interferes with the learner's attempt to incorporate new, correct
knowledge that is to be learned into that which is already known. Learning
requires "repair" of existing mental representations (models) to correct mis-
conceptions while simultaneously extending the model to include new con-
cepts. Thus, learning is often talked about as representing a process of
"conceptual change" (Smith, 1991).
In thinking about learning, it is important to recognize that there are at
least three different kinds of "things" that can be learned: (1) declarative
knowledge, (2) procedural knowledge, and (3) psychomotor skills. As we
will see, all three have been extensively studied by the learning sciences.
Declarative knowledge is the "what" of a particular topic. It can be a set of
facts that defines aspects of the subject matter. The facts can be as simple as
the definition of terms ("amino acids are ... ," "the resting potential is ... ,"
"igneous rock is ... ") or a collection of data ("normal mean arterial pressure
is ... ," "the equilibrium constant for this reaction is ... ," "the value of the
gravitational constant is ..."). Declarative knowledge can also be more com-