I guess the math is something I can relate to our daughter.
When she was in 7th grade, she said she wanted to skip the 8th. (I had no doubt she could) I told her she needed to do ALL the preparations for this, and to keep us up to date on what's going on.
I can't remember exactly what all was involved, but I know she arranged meetings with a few teachers, and the principal, the school counselor, handled it all herself.
Then one day, she came home from school and said she's going to be a freshman next year!
We totally let her do what was necessary to get what she wanted, to happen.
Her older brother was in a junior golf league in the summer, starting at age 10, and basically took care of that too. There were about 15 tournaments in the summer. It was his job to get a list of were he wanted to be, and arrange it with me, to make sure I wasn't running around with another kid.
Your son is eleven. That is exactly the age that I've found that boys have to do 'man' things. I learned this when our oldest took an ax and chopped the garden hose in 2.
The HusbandHalf and I talked about it, and decided our prior 'hardly got into any trouble 11 yr old,' needed something that would feel like he was growing, he should be able to do more grown up things. So, we had a tree out back, maybe 6" in diameter that we thought could be chopped down for such an important lesson, and let him have at it. Took him all summer, but he chopped down that tree - like a man! He got a little older and THH showed him how to run the chainsaw.
He had run the John Deere lawn tractor sporadically, but it was now his job, and later his little brother's, to mow the lawn.
We had a wood chipper at the time, so after a lesson from THH, he was in charge of taking care of limbs on the lawn. It was his job to keep the lawn free of limbs, and put the mulch he made on the beds of flowers. There were times that were fun too, throwing old zuchinni in the wood chipper, mowing the grass FAST (but safe)
THH and I should have thought of this need on our own. When I was growing up, my Dad restored old cars. When my brothers were about 12, they got what looked to be a piece of junk. When they were 16, they had '57 Chevy, a 50's Ford, and I can't remember the other.
THH told me just yesterday, when we drove by a house, that he dug around the foundation when he was 16. He did many different physical jobs, that he got paid for, when he had the 'need to do man things' feeling.
I do not know what a parent would do today, in their situation (city?) but I suggest thinking of things your son can do, to take care of his need to do grownup stuff.