Investigation skills are taught for several reasons--to help students become better thinkers and problem solvers; to help them be better versed in the nature of scientific work; and to help them remember content and facts. We know that students do not learn new science skills in observation, for example, without explicit attention to the skill. Simply observing something does not improve observation skills. Yet almost every major commercial curriculum will rattle off all of the process skills in a lesson when none are directly taught. Throughout this issue, the aim is to fill some of those gaps.