Your son needs to know his flowchart, be familiar with his upcoming classes, and be aware of what’s expected of him GPA wise. I know my flowchart, what concentration electives are offered, the general timing of courses, and the rough prerequisites for my courses, and when I plan on taking them. This kind of familiarity helps prevent being blind-sided by not having a prerequisite or being three credits short on a requirement.
Like noted before, it really helps if you’re able to speak with your advisor. They’re there to help you. Professors can help, as well. Once you get into your higher major courses it makes a difference sometimes with your course loads and such.
My mom isn’t really involved with knowing my degree requirements. I’m not sure she even knows how many credits my degree requires, but she knows I’m on track and doing what I need to do. It’s a system that works for us. She checks on me while I’m taking the classes ensuring that I’m getting help when I need it, rather than after the fact when a course has already been completed.