Youth who lack a stable environment are vulnerable to a number of adverse outcomes, such as poverty, hunger violence, and mental illnesses. These factors are causes of episodes of homelessness. Homeless youth are more likely than other youth to have acute and chronic health problems. They have less access to medical and dental care. Youth are sustainable to asthma, ADHD, and behavior problems. Youth without stable homes are more than twice as likely as others fail classes, get poor grades or drop out of high school.