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.