I have actually floated that idea to him. That seems like a pretty good industry. He's really good at math but doesn't love it, if that makes sense. So, maybe that's not for him, though.
Being good at math but not loving it probably suggests no on the actuary.
My advice is to look at the research going on at the university by the different faculty members in the engineering departments (and maybe beyond engineering). Even if he has no or little interest in grad school, it can give him a feel for the area he wants to pursue, maybe find some faculty or grad students to mentor him and possibly employ him.
The range of jobs within an engineering discipline are wildly diverse. An ME grad might be doing process engineering, they might be doing product design, or they might be doing computational fluid dynamics.
So I think which discipline in engineering is probably not the place to start, but rather look at research by different faculty, find some areas of interest, and talk to that professor.
The point is the experts in a field at a university might not be in the department you would expect. Two examples at ISU right now are that the renewable fuels expert is in ME, and the plastics recycling expert is in food science.
My second bit of advice is related and somewhat contrary to the advice here a bit, is that once he finds something he's interested in and a professor engaging in work in that field, he should try his damned to get a job working for the grad student and/or professor. Do that for a couple of years and it will dwarf almost any summer internship a kid gets in the eyes of a future employer, that is unless the internship is with that future employer. So I disagree with the view of taking multiple internships. The reality and view by many employers regarding internships are:
- They can range from terrific to completely worthless. That depends on the company, and who a kid is working with in the company. Years ago I worked for a company that had tons of ISU interns. Some got great experience, some were a complete waste of time because the people that committed to host them either left the job, forgot, or didn't have anything for them to do.
- To completely flame out of a summer internship, you have to be pretty horrible. You can be pretty bad and make it through a summer getting by. Not to mention a company might look and say, "this guy interned at Company X. If Company X doesn't want to hire him, he must not have been very good."
Conversely, if you work for a professor in a field for two years, you not only bring great experience, you have a track record that shows you are a good employee.