Please don't "protect your GPA"
Teaching at a competitive state university, I see a lot of freshmen arrive on campus with a 4.0 (or higher!!) grade point average (GPA*) from high school. This has ceased to impress me because so many of them report that they earned that GPA by 'protecting' it. They tell me that they would only enroll in classes when they knew they could earn an A. They tell me that they would drop a class if they were earning anything less than an A.
Did they do well in their classes? Of course. But what have they missed by focusing so intently on protecting that GPA? That strategy was successful in high school and earned them a place in this competitive university. They are often intent on continuing doing what has worked so well in the past, but I beg them to reconsider this strategy at university.
When they have their degree in hand and are applying to a job or a place in grad school, the candidate who reports that they earned a 4.0 in high school and university by not taking any risks is simply not going to be successful. I would hands-down hire the candidate with a battered 3.0 and a compelling narrative about struggling and taking risks and learning from failure. Nobody wants a grad student or employee who will abandon a project that doesn't instantly succeed. We need people with the grit to preserver. And you can't get that grit by protecting a 4.0.
So, call your parents (or call your student) and lay out a plan that will include you enrolling in a class that you are not sure about. Stretch yourself into a topic out of your comfort zone. You may find something that changes your life or you may only find out what it takes to struggle. Bring home a 'C' and bake a cake to celebrate your amazing achievement. Believe me, it will make for far more interesting conversation during a job interview than reciting your strategies for protecting your 4.0.
The Economist had some far more eloquent thoughts on this topic.
*For those who aren't familiar with this system, in a modular high school system, students earn grade points for each unit in each class in each semester. The average of these grades is reported. These are often calculated on a 4.0 scale:
A = 4.0
B = 3.0
C = 2.0
D = 1.0
F = 0.0
Students will graduate with a GPA higher than 4.0 by taking Advanced Placement classes that allow them to earn off-scale points.