Once again, thanks for all the advice. It was very helpful. At this point, he planned a curriculum for the spring semester that still buys him another semester to decide by taking a bunch of math courses he needs for both options. He will also do either a summer internship or UROP (on campus research), and talk to frat alum and recruiters over the next semester to help him choose between the following two options for how he wants to spend his undergraduate years:
1. B.S. in Mathematics with Computer Science and B.S. in Management Science (double major).
or
2. B.S. in Electrical Engineering and Computer Science