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A lot of research shows that there are lots of benefits of preschool education. treated children stary is school loger have better grades, are happier, pay more in taxes, have better education and are more fit physically. I want to measure their of subjectimve wellbeing and compare their subjective wellbeing to a cohort group which did not receive preschool. I'm having difficulty putting these into words and finding the appropriate research (literature review)