Great title, Faith! Congratulations to your son and nephews!
I went to FOUR grad. ceremonies one year! Ugh!
The best one was the "alternate" high school my son graduated from. He sounds a LOT like your son: No dummy, just uninspired and won't do the work.
That (now grown) son has surprised me by being an electrical apprentice for 3.5 years now, which means he works and gets paid. In addition, he takes a couple of college classes. He gets straight A's! In another semester he'll be an electrical journeyman!
I guess it just amounts to their being interested in what they're studying, so that they study and do the homework.
And being middle-aged? Well, that just depends on how long you plan on living: for instance, if you plan on living until age 120, then you're not technically middle-aged until you're 60!