One of the items that is becoming more and more important for all students is to build a professional portfolio with volunteer and work experience related to their future career. Where this comes into play is getting into relevant internships and professional schools. It is never too early to start.
These experiences can take many forms, from club memberships, leadership position in clubs or other organizations, shadowing professionals in their chosen career, working in labs, summer jobs, etc.
As an example: a CSS chemistry graduate, worked in a research lab the summer after his junior year. From this he received partial authorship of a scientific publication as well as a great letter of reference. This all helped him get into Graduate school. I recommend you really encourage your son or daughter to visit with their advisor to talk about this.