So I got thi baby sitting job. it is for 4 days. and there are 4 kids. how much should I charge?

It depends on their respective ages and whether or not they'll be at school during any part of the day, giving you some free time. Also, you can factor in gas costs if you need to drive them anywhere. And the fact that they will probably be paying for the food you eat and giving you a bed to sleep on if you're staying at their house. Personally, I wouldn't charge less than $80-$100 per day. I mean, a 5 hour babysitter for 2-3 kids usually gets $20-$25, so multiply that but take off some for food and give them some sort of discount because of the length...

I was gona say 30 dollars a day but 10.00 dollar an hour sound good too!

It depends how long the days are, how much they are expecting you to do. I would charge about 8-10 dollars an hour, considering there are 4 kids and you are older with a lot of experience.