@curiositycat333
I do not think the faculty distinguish or care which college a student in their class is part of, A&S or Engineering.
In fact, many majors in A&S such as physics, outranks all engineering majors, if you care about ranks. Engineering college is well ranked though.
Note here the two sets of students, A&S and Engineering college, are mixed into the same CS classes:
http://www.colorado.edu/cs/current-students/undergraduate-students/ba-degree
The only thing to be aware of , he will earn the BA degree, no matter how many CS classes he takes, even if
he takes enough to earn a BS, if he stays in the Arts and Sciences college. He may want to transfer, perhaps,
but it may not matter, again, see that the classes are IDENTICAL, so I do not see why he needs to transfer unless he just really wants a BS degree.
No professor is going to track which college individual students are enrolled in, classes are lecture style
and no one will care about that.
(The math sequence may be different though depending on exactly which major he selects, Engineering calculus versus calculus is slightly different)
CU Boulder will not shut him out of a computer science major. CS is growing but not over crowded yet.
No majors are “impacted” at CU Boulder, the school actively looks for students from OOS and international students to fill up any major. And the school is increasing in size and hiring faculty in engineering and CS.
Colorado has many in state options that are equally affordable to CU Boulder so Boulder actually has plenty of room.
The only restriction would be if he wanted to major in computer engineering, he would have to transfer to College of Engineering , here is the process:
http://www.colorado.edu/engineering-advising/transfer-within-cu
CU Boulder registration is not very difficult I have heard. Some students do enroll in summer school as its so inexpensive for in state. I don’t know how that works for out of state students, you could check on that. There is May Semester (one class , in three weeks)
http://www.colorado.edu/summer/courses/3-week-intensives/maymester
and Summer Semester, so two shots at taking summer classes. There is also a state rule or law that says undergraduates at CU should have classes available to finish in four years, I don’t know how well that is enforced, but I think that means you cannot be shut out of a class that is REQUIRED for your bachelors degree. You may be shut out of art history, or say tuba performance, if you are not a major or minor in those subjects .
I taught one semester at CU in Chemical Engineering as an adjunct and I was allowed to increase the size of my class on my own and I did that. Students emailed me asking, and I told each one, yes, they could register. That was ten years ago now, but I suspect that had not changed. So the class was supposed to be capped at 60 but I increased the size to 70 students. I believe that is still how it works , so teacher discretion allows more kids into a class, and CU will give the class a larger lecture hall if needed. This may not hold in the College of Arts and Sciences. Sorry I cannot be more helpful. My own children are not at CU, so I don’t have personal information about the registration process, but not hearing any complaining from my son’s friends. Most are in the college of Engineering, though. Music is small and easy to register if you are a major. I am not certain how it works for minors, I would ask about that. Majors are going to have preference over minors or nonmajors in the College of Music.