As part of my PhD programme I worked within my department as a teaching assistant for the following courses:
Introduction to Topology (third year undergraduate course, Spring term 2018): assisted the lead lecturer during supervision classes, helping students with exercises.
Introduction to Pure Mathematics (first year undergraduate course, Winter term 2018 and Spring term 2019): lead a supervision class myself for 10-15 students, discussing lecture material and homework exercises.
Linear Algebra (first year undergraduate course, Spring term 2019): lead a supervision class myself for 10-15 students, discussing lecture material and homework exercises.