Oleg,
You want him motivated and in the outdoors? Here is the answer. I was the same type of dude at that age.
The answer: Northwest Youth Corps. It was run out Eugene, OR when I was there. What is it? The teenagers all work in the forest when I was there. What did we do? We did trail maintenance. We cleaned up after logging companies. We did something called vexar tubing (to keep the animals from eating new trees). It was a 5 week course. You could sign up for more. But mostly in the summer. Everyone is a teenager but the crew chief and they were typically college students. You sleep in a tent, wake up, do hard work for 8-10 hours, then you go back to your camp. Only on weekends did we shower at campgrounds. We never went home. Sometimes the parents showed up on weekends. Sometimes they didn't. By the way, Northwest Youth Corps is a paying job - not volunteer.
Another thing. I wonder if he is thinking about a car? Show him how to get the money for the car. Show him your insurance. Maybe he needs a job for the car?
Another thing. You are doing more than you know.