You would benefit from speaking to your local Domestic Abuse Service. He is an abuser. He is coercively controlling, emotionally abusive and financially abusive. You need support and your teen does too. Domestic Abuse services are not just for physical abuse, most of their work is coercive control etc.
Keep a paper diary of everytime he contacts you, what his demands are, how you felt, the kids reactions etc. Contemporaneous notes will show how he's is being unreasonable. Hide your diary.
You need a separate phone that you turn on ONLY ONCE A DAY. Block him on your personal phone. Let your teen know its ok to turn off phone or block/unblock their father. Its important they know they can say No to their father. Tell him you have changed your email and set up a separate email just for him, nothing else. That way you won't start reacting everytime you get a normal email notification and you have further evidence of attempts to control you.
Does your school operate a Parent Mail App system, where each parent receives an email with dates etc? You can inform the mediator that he is unreasonable in his requests to know every detail of your day, that you feel this is controlling behaviour, especially as he does not reciprocate with his plans. Also, inform the mediator in writing with a copy to your ex that as the school information is freely available, you are busy working and looking after the house and children, you are no longer able to provide "secretarial support" to your ex. Suggest his Mum takes on the role if its too much for his manly brain!
Your time with the kids is your time. You no longer need to jump everytime he texts, phones etc. It's OK not to respond immediately or even that day, and when he whines tell him its not his business what you were doing. Rinse and repeat. You no longer have to do anything he says. He has trained you but you can now refuse. Let him make himself look unreasonable with all his demands. YOU ARE FREE.
The Courts will listen to what the children want, especially the teen. My solicitor laughed when I told her he was threatening family court with teens. Especially if you have support from the Domestic Abuse service.
Put a chain on the door, so he can't let himself in unannounced and leave a key permanently in the other door so it can't be opened from outside. You are a woman alone with children, it's not unreasonable to take small measures to provide protection for yourself and your children. Get a ring doorbell to show him snooping around. After I went to DAS and solicitor, I was told to change my locks. My solicitor said I could call the police if he kept trying to get in, even though he owned a share. You are allowed peaceful enjoyment of your own house. He's moved out, there is no need for him to keep coming back. Yes, legally he may be able to but its further evidence of his control and bullying. Document everything and hide your private papers in lockable box, keeping the keys on you.
If he follows you home after clubs, stop going home! Pop to the supermarket, drivethru and sit in car to eat and chat to the kids about their day, (just buy one chips to share if you cant afford more). Or go to see a friend. If you explain the situation, I'm sure they will provide sanctuary and a coffee whilst he gets fed up of waiting and goes away. And note it in your diary and the kids comments. Its not his time so you do not need to provide access to kids. Stop allowing control over you.
Stay strong. You can say No and he has to lump it. It will get easier. Allow him to make an unreasonable fool of himself. The solicitors and courts are used to hearing abusive men accuse women of abuse, it's DARVO. Get support. You will get through this and life will be so much better. Promise.