They are learning how to identify biodegradable garbage, how to make compost, and how to water the trees they have planted in the schoolyard.

VOA: standard.2010.04.01

How can we prevent murderous schoolyard violence in children who have access to weapons,poor parental supervision, and a mean streak?"

如何防止校园暴力,这些暴力事件通常是由掌握武器，缺乏父母监管，或受到教唆的孩子引起的“

哈佛公开课 - 幸福课课程节选

How can we prevent murderous schoolyard violence in children who have access to weapons,poor parental supervision, and a mean streak?"

如何防止校园暴力,这些暴力事件通常是由掌握武器，缺乏父母监管，或受到教唆的孩子引起的“

哈佛公开课 - 幸福课课程节选