Can someone please explain to me why I am not allowed dating?

Me and this girl like each other, but I'm not allowed to date until grade 11, in 5 months. I'm 15, close to 16, and all my friends were allowed to date whenever they wanted to but I have to wait until grade 11. I don't understand why because of all my friends I am one of the most behaved, well mannered, mature, smartest and hardest workers. I also believe I am emotionally ready. I'm also Asian if that has anything to do with it.