The use of questioning to elicit student thinking is one of the cornerstones of ambitious teaching; thus, supporting prospective teachers in this complex practice is a core objective of mathematics teacher education. In this paper, we examine the academic rigor of the sustained questioning sequences prospective teachers use during instruction to elicit student thinking and the possible factor lesson planning plays in enacted sequences involving academically rigorous questions. We analyzed the questions they asked during lessons in an early field experience and traced how prospective teachers prepared for those questions as represented in their lesson plans. From our analysis, we found prospective teachers used three types of sustained questioning sequences when eliciting student thinking in the enactment of the lesson. Further, we found evidence suggesting a connection between the questions asked during enactment of a lesson and the quality of questions prospective teachers incorporated into their lesson plan. These findings inform how mathematics teacher educators can support prospective teachers during lesson planning to prepare to elicit student thinking in productive ways.