ABSTRACT
In this chapter we consider the way children understand a number of scien tific concepts. We begin with the balance scale because of the longstanding interest in it, and because there is plenty of high-quality research to constrain theories of mental models for this task. We then consider a number of kinemat ics problems, with special focus on the way children understand the relations between time, speed, and distance, their concept of motion, and the differen tiation between speed and acceleration. Then as an example of a complex kinematics problem, we consider the Rutherford analogy between the struc ture of the atom and the structure of the solar system. We consider the appearance-reality distinction because it is basic to scientific thought. The themes of knowledge organization and structural complexity, together with their interaction, are present throughout the chapter.
