With my older two we (dh and I) drove them and waited in the car each year. (Actually for dd2's A level results, she asked me to come into school with her and then didn't want to open the envelope, and her favourite teacher just told her her grades!)
Ds however is insisting he's going by himself, doesn't want any company on the way to school, etc. So at the moment that's the plan. Will feel very strange going off to work and waiting to hear from him.