He sounds bored.
Is there any reason he needs to do more at this point? What’s in it for him?
What kind of career goals, if any, does he have? Are they related in any way to what his school wants from him?
Is he chatty or quiet? How long can you not talk? If he’s chatty, listen carefully to what he says for the next few weeks. He’ll tell you what he needs. If he’s quiet, spend as much time with him as you can, not talking. Do something that’s easy to interrupt when he wants to talk. In both cases, once he trusts that you won’t nag, judge, lecture or discipline, he’ll likely tell you why he does what he does.
By the time I was his age about 100 people had told me I was bad for things totally out of my control and related to ADHD. Most assumed I was too young to know what I needed. It takes time to rebuild trust. Trust is pretty much only going to be rebuilt by parents behaving in a trustworthy manner consistently, over time
Like it or not, it’s pretty much on us parents, which can be very difficult if parent also had ADHD!