Prior research has shown that orchestrating scientific discourse in classrooms is difficult and takes a great deal of effort on the part of teachers. In this study, we examined teachers' instructional moves to elicit and develop students' ideas and questions as they orchestrated discourse with their fifth grade students during a learner-centered environmental biology unit. The unit materials included features meant to support teachers in eliciting and working with students' ideas and questions as a source for student-led investigations. We present three contrasting cases of teachers to highlight evidence that shows teachers' differing strategies for eliciting students' ideas and questions, and for developing their ideas, questions and questioning skills. Results from our cross case analysis provide insight into the ways in which teachers' enactments enabled them to work with students' ideas and questions to help advance learning. Consistent with other studies, we found that teachers could readily elicit ideas and questions but experienced challenges in helping students develop them. Findings suggest a need for more specified supports, such as specific discourse strategies, to help teachers attend to student thinking. We explore implications for curricular tools and discuss a need for more examples of effective discourse moves for use by teachers in orchestrating scientific discourse.