The Department of Mathematics Education, Faculty of Mathematics and Natural Sciences, Yogyakarta State University, successfully held Webinar Series #1 2024. This webinar was held on Saturday, August 10, 2024 with the theme Psychology of Learning Mathematics and Differential Learning. The event was opened by Dr. Kuswari Hernawati, S.Si., M.Kom. She conveyed the purpose of this Webinar Series #1 to dig deeper into how to improve the quality of mathematics learning through understanding the psychology of learning and the application of differentiated learning, and it is hoped that new insights and strategies can be applied in daily teaching and learning activities. The first speaker, Dr. Teguh Slamet Wahyudi, S.Si, M.A., M.Pd., M.Ud. delivered material on the topic "Psychology of Mathematics Learning Practices in High School". He conveyed his initial intention to become a teacher as outlined in his book entitled Call Me Dad. He also conveyed the contents of an inspirational book entitled Quantum Teaching which can be practiced in the classroom.

The first session lasted for 45 minutes. After that, the committee invited participants to take an interactive ice breaking quiz to calm the brain. The participants who attended were very enthusiastic about participating in the interactive quiz which was guided by the Webinar Series #1 Technical Team. Not to forget, attractive prizes were distributed to three selected participants who answered correctly. After ice breaking, the second speaker, Mrs. Dr. Djamilah Bondan Widjajanti, M.Si. delivered material on the topic "Maintaining Student Psychology in Differentiated Learning in Mathematics Classrooms". She explained that students have diversity in several ways in the classroom. Here the teacher's job is to help each student to be able to achieve their optimal achievement. Then, he also conveyed how the practice should be done by teachers when teaching in the classroom. More complete material can be listened to on the youtube channel math_education_uny. The next session was delivered by the resource person Mrs. Endah Retnowati, M.Ed., Ph.D. with the topic "Differentiated Learning from the Cognitive Load Theory Perspective" Where the contents of the discussion, including Cognitive Load Theory, Intelligence, Research in CLT, and Differentiated Techniques and their reflections.  The last session was a question and answer session and ended with the awarding of certificates by Dr. Kuswari Hernawati, S.Si., M.Kom. This activity is carried out virtually through the zoom application and live broadcasts on the math_education_uny youtube account. With this year's Webinar Series #1, it is hoped that the audience can develop, think, and increase new insights about the psychology of mathematics learning that can be applied in teaching and learning activities.