It was called the Perry Preschool Project, and it found that toddlers who attended preschool, even part time, go on to greater academic and job success in life than those that didn't.
Excerpt:"You might not think of soft skills as skills at all. They involve things like being able to pay attention and focus, being curious and open to new experiences, and being able to control your temper and not get frustrated.
All these soft skills are very important in getting a job. And Heckman discovered that you don't get them in high school, or in middle school, or even in elementary school. You get them in preschool."
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