I'm preparing my CV for applying to a MSc program in a specific Computer Science field. In the section of "Working experience" I've written about my work placement and the main job I've had the past few years (both are related with my field of studies). However, in addition to them, I was a lab assistant in my department for a whole semester. My question is, should I also mention this as a working experience? If not, what is the best way to include it to my CV?