I've been occasionally babysitting this kid for about a year, it used to be about once a week for around 4 hours but since its summer it's been more like twice a week for 9 hours each day. The parents give me the days they need me about 2 weeks in advance and give me the days they need me for the next few months. They expect me to come those days and never even gave me notice that the days would be so much longer than before. I also have 2 other jobs, which are more important than that one, and I need to quit this job for myself because I'm too stressed and starting college soon. They already gave me the schedule through August, and I feel obligated to stick it out until then, but I really can't do that. I need help formulating a reasoning to give the parents because I feel so obligated but I'm just sooo stressed.