Here are you options:-
1.Do nothing
2.Leave by 1700hrs as suggested, alone or with your kids
3.Sit down, take inventory, figure out where the rain started beating you. Try counseling as MC suggested above. I will suggest you go this route only and only if he is willing to go for counseling too otherwise utakuwa unapaka mbuzi rangi.
4.Sit down, plan an exit strategy. Your plan is to leave in the next 3-6 months, by now you know the things that provoke him to hit you or fight with you, try as much as possible to avoid them, this requires a lot of pretense, you see things but do not complain about them, avoid sex without protection if you can. the whole idea is to buy yourself time to plan your exit, where you will go, do you want to change schools for the kids etc. etc. Also this is the time to start healing yourself and it will help when you start living alone, this is not going to be easy but if you prepare yourself, financially, emotionally, and psychologically it might be bearable, otherwise you will walk out and walk right back, something i detest.
5. If you have considered 4 above and are financially in a position to support your kids, get yourself a house somewhere else, scout for schools for your kids for next term possibly, walk and never look back.
6. If you have considered 4 above but are not financially in a position to fend for the kids but can afford to rent a house somewhere, move out with the kids and haul the bugger to court for upkeep.
7. If 6 above is not possible, go back to your parents home with your kids and take the bugger to court for upkeep.
All the best.