"Thinking originates from problems", and problems are the heart of mathematics. If there is a problem, we should solve it, and students' thinking will become active. Problem-based teaching makes the classroom full of suspense and vitality, can fully mobilize students' enthusiasm, let students' thinking accept challenges, and let students' potential be fully tapped, thus cultivating students' autonomous learning and inquiry ability and improving classroom teaching efficiency. Therefore, experienced teachers always carefully design questions in the process of mathematics teaching, try their best to ignite students' thinking sparks, stimulate their desire for knowledge, consciously set up steps for them to solve problems, and guide them step by step to the palace of knowledge. I talk about the present situation in combination with my own teaching practice. First, the creation of problem situations should stimulate students' interest in learning, because interest is the best teacher, and mathematics classroom teaching is the easiest to take the form of "teachers talk and students listen", which is boring and has little effect. Therefore, in order to improve the teaching effect, the creation of problem situations must be aimed at mobilizing students' learning enthusiasm. Small mathematics experiments can be used to stimulate students' curiosity and thirst for knowledge. For example, when talking about the triangle interior angle theorem, you can set questions like this: ① Cut the △ABC paper-cut before class, and cut ∠A, ∠B and ∠C together to see what angles they can form. What conclusion can you draw from this? What inspiration did you get from the puzzle?