I can’t speak for Computer Engineering at TAMU, but here is my story. Back “in the dark ages” when I was in college, (different U, different State) I went through something like your son is going through. I had always easily made great grades without studying and was Salutatorian of my HS, BUT my HS was a poor performing HS and I had never learned how to study efficiently.
After my first shocking Semester of college, I ended up taking biofeedback classes (as part of a project administered by the Psychology Dept. and referred by the Student Health system) in order to deal with a sudden case of overwhelming Math Anxiety. I went to every professors office hours and joined study groups. There was no tutoring available that I was aware of, and I couldn’t have afforded anything that cost extra anyway. I had Work Study as part of my Financial Aid, so I had little extra time, but I struggled on. It was humiliating at first, but I eventually learned how to study efficiently.
And sometimes, having a good professor was the key. I flunked OChem the first time that I took it. I made a C on the first test (which was actually a great grade in that class) and when I went to that professors office hours, he shocked me by saying that “if I spent 5 minutes with every student, I wouldn’t get any research done!!” So that Semester, I focused on my other classes and made As in those classes and an F in OChem. When I repeated OChem, I had a much nicer professor who took time to explain and I made an A. I saw my first prof in an elevator and told him I was making an A in OChem with a BETTER PROFESSOR and he was shocked! If tutoring had been available/affordable for me, I probably could have pulled off a C in the first OChem class even with a rotten prof, but my other classes would have suffered during that semester. I graduated a couple of Semesters “late” with a gpa above 3.25, about in the upper third of that class. And later in life, at age 30, I joined Mensa.
A high IQ does not mean that EVERYTHING will ALWAYS come easily.
Is there a particular type of class that he is having difficulty with? Is it the core curriculum or his Computer Engineering major classes? Is it writing papers that is difficult or Math/Science? See if there is a pattern to his difficulty. Maybe there is something that his HS just did not teach him. It does sound like there is something that he is missing. Your son may think that he is studying efficiently, but what worked for him in HS is obviously NOT working for him at TAMU. It is time to change the plan.
Even though he is adamant that he is studying efficiently, it sounds to me like tutoring would be a BIG help. I have friends whose children were TAMU Engineering students (neither of my daughters are) and they insisted that their children go to tutoring from their first through last TAMU semesters, even when they were making As. Even if they only worked on Homework at the tutoring sessions, it was worth it to them. That way, if the student had even one question, there was someone nearby to answer that question quickly and that meant less time wasted. But also, if there was some concept that the student just wasn’t getting, the tutor could help them with it BEFORE it showed up on the final! There are a lot of great tutoring places near campus. A LOT of people go there, there is no shame in getting tutoring. It is a lot more stressful to work hard and still not make good grades. There is help available for writing papers that I think is available on campus. Check out all of the resources available and have him choose where to go.
I wouldn’t worry about having him take longer than 4 years to graduate. A LOT of people take extra time. And hopefully, he is in the appropriate major for him. Maybe now that he knows more about that major, perhaps there is something else that fits his unique interests/strengths. Teenagers shouldn’t have to make a decision about their majors before they even know what else is out there in the big world.
Having some 'down time" and some sort of fun activity is also necessary for his mental and physical health. If he is just studying all the time, he is not studying efficiently and the stress isn’t good for him. If he is playing too much, then he needs to cut back on the fun stuff. He should have a healthy ration of fun time to studying time which will also equal good grades.
There is no life badge earned for continuing to struggle on his own when there is help available. He is not lost and alone in the wilderness or a deserted island or sinking ship, where he would be just trying to find enough food/shelter/safety to survive minute by minute. He is at a major US University where there is abundant help. He just has to utilize it. If he was lost and alone in the wilderness, would he turn down readily available help? Would he say “No thanks, I want to survive on my own, I don’t want your help?” Probably not.
I hope it works out well for him.