It’s better if you do – you will learn a lot. However, some people think it will be too upsetting to talk about these issues. If you think it might upset you, discuss it with a parent or another trusted adult. You need to talk to your classroom teacher about what arrangements will be made for people who ‘opt-out’ of the course – often this will be a study period in the library or something similar.
If you are being offered the course outside of school, you'll need to talk to the organiser about what you'll be doing if you don't attend the course.