What is the difference in terms of job description between a child psychologist and a school psychologist?

Nothing. The only differ is the college classes electives for whatever field of Psychology you want to go into. There are many fields of Psychology. Such as Marriage Family Therapist Counselor, School Counselor or guidance counsleor, Coach for jobs. Psychologist for mentally challenged individuals, You can not write any prescriptions being a psychologist. As long as you get a college bachelor's or masters degree in Psychology you will know what to go for after all of you prerequesite classe's are completed. You have many choice's more now than ever to choose what type of Psych. like abnormal psych, social psych, forensic, psych, criminal psych. medical assistant psych. You have many choices. Good luck. I would get all your pre education credits at a community college then transfer to a four year university or college if you cannot afford to go to a four year college right out the door. Either way there is much funding out there to help you with the prospect of whatever you decide to take. I am sure you will have high school guidance counsleor help you with the process.