Structures, vibrations, aerodynamics, materials are the most common specialties
in my world. There are many good paths to get there. I’ve worked with many good engineers from numerous schools (Georgia Tech, Mississippi State, Stanford, NC State, Virginia Tech, Ohio State, Texas, Wichita State, BYU and more). While BYU does not have a specific Aero program, it will provide a solid foundation in mechanical structures with the right electives.
I would choose the school and choose electives that will put him on the path that most interests him. My preference would also be to attend a school that had athletics…big part of the fun of college.
As an example, if I were most interested in composite materials and exposure to research and testing then I would look into Wichita State (shocking…pun intended).