In this article the authors discuss some basic research on the inquiry abilities of elementary students and draw implications for curriculum policy and teacher professional development. In their research, they asked students to make investigations and compared the abilities of students who have had hands-on inquiry science curricula with those of students who have used science textbooks. They state that they should emphasize that developing inquiry skills is only one aspect of the curricula, and the comparison is not between the two types as a whole. And content learning, effects on student attitudes, and building communication skills are other very important aspects of the curricula only marginally addressed in this study. (Contains 1 figure and 13 endnotes.)