Have you looked into the NUPOC program? I am currently in the NUPOC program and from skimming the thread, I think it's exactly what you are looking for. If your son goes to college majoring in engineering, math, chemistry, or physics, he could apply for NUPOC (Nuclear Propulsion Officer Candidate) halfway through his sophmore year. He would go on a VIP trip to King's Bay, GA to tour a sub and a carrier. If profesisionally reccommended, eventually he would go to DC to interview with NR Engineers and Director, Naval Nuclear Propulsion. ADM Bowman was the Director when I interviewed, but ADM Donald is the new Director. If he gets in, it is really a great deal. You get a $10,000 ascension bonus and starts drawing pay and leave as an E-6. If he then recruits someone who gets into the program, he would become an E-7.
There are four routes you can go in NUPOC: Sub/Surface, Instructor, and Engineer. Sub candidates go to OCS (12 weeks) after they graduate to get commissioned, then to Nuclear Power School in Charleston, SC for 6 months, then to Nuclear Prototype in either Charleston or Ballston Spa, NY for 6 months. Finally, 13 weeks in Groton, CT for Sub School, then to the fleet. Surface candidates go from OCS to a conventional ship for ~21 months, then Nuc Power School/Prototype, SWO school, then a Carrier.
I am going Sub so I am pretty familiar with the Sub/Surface routes. For Instructor and Engineer, they go to OIS (5 or 6 weeks), then Nuc School. I don't know whether they go to Prototype, but I know they then go to either teach at Nuc School or work in DC at the office of the Director.
If your son is really interested, it is a great opportunity. Feel free to email me (thgardn1@vt.edu) if you would like or you could just contact a local recruiter who could give you plenty of information.