Advice from a junior in high school

I don't think the conventional methods you're trying, such as cutting him off from the internet, ever work effectively. This is because these conventional methods simply resolve the symptoms of his root problem temporarily. As soon as you don't keep an eye on him or loosen the rules, he will go right back to wasting time. Instead, what you should be striving for is identifying his root problem and give him the means to solve it on his own. For example, one such root problem might be feeling like he has no control over his own life. In your post, you said that you were planning his time[安排都不愿意配合], so he might feel stifled and feel like he has no control over his own time. Therefore, instead of setting strict times he has to finish homework or other responsibilities, you could give him a list of all his responsibilities for the week and have him plan out every week realistically on his own, and only enact a punishment if he doesn't follow his own plan. However, there are many different reasons why he is acting up. So try to identify what problem he has personally and point him in the direction towards solving it himself. This will rid him of his root problem most effectively and thoroughly.