Investigation involving children's understandings of scientific concepts have been a dominant area of research in science education over the last 2 1/2 decades. One fruitful outcome of these studies is to alert teachers to difficulties in learning science. Although this information is commendable in highlighting their existence, not much is presented on how to deal with the alternative conceptions. It is generally believed that teachers tend to teach the way they were taught, and breaking this cycle requires different emphasis on pedagogy in teacher education. The focus of this article is on preservice teachers' experiences in a science education course as they explore the importance of children's alternative conceptions and in using such knowledge to make decisions about teaching.