Teacher questions in mathematics learning can foster student understanding, especially teacher questions in small group discussions. Through the small group discussion method, teachers can specifically provide assistance to students more intensively in understanding learning materials by giving questions. There are 4 types of teacher questions in group learning, including convergent questions, divergent questions, probing and follow-up questions and evaluation questions. Based on the results of the study whose data were obtained from the analysis of learning videos conducted by a group of mathematics teachers consisting of 3 junior high school mathematics teachers and special interviews with teachers about the impact of teacher questions on fostering students' potential understanding, it was found that probing and follow-up questions were asked by teachers to help students solve problems in small group discussions. These questions direct students to understand the learning material and can be used as a reference in order to improve student potential.