Sure you do! Let me give you a head start--I will follow up and use these too! Seriously.
Goal #1 - Block as much communication as possible/ practical. For me I would also block your childrens for the time being. Long enough to establish some normalcy for them without him constantly butting in and being jerky. Really even a week would be good to let everyone cool off and calm down.
Goal #2 - follow up with child support to be sure it is happening. Also- Check your state- mine has tough support laws- use those to your advantage.
Goal #3 - Do what you have to in order to ensure a safe environment for your children - change locks, consider restraining orders, whatever you need.
Goal #4 - Please be certain to talk to your kids' school and let them know the situation. If you get protection orders be absolutely certain they are aware of it to.