B．They are learning about eating healthily.

　　C．They are learning how to pick out fresh vegetables.

　　D．They are being punished because of their poor performance.

　　解析：选B　细节理解题。由第一段"Instead, they are tasting kale ... the first time."和第二段第一句"The school's teacher Dionne Hammiel says ... habits from the program."可知，孩子们放学后还没走，是在学习健康饮食。

　　2．What do we know about FoodCorps?

　　A．It makes money by selling healthy food.

　　B．It helps a lot in fighting against childhood obesity.

　　C．It teaches students how to plant healthy vegetables.

　　D．It aims at introducing rare vegetables across the United States.

　　解析：选B　细节理解题。由最后一段"She says the group's work is especially important in the fight against childhood obesity ..."可知，FoodCorps在解决儿童肥胖问题上的贡献尤为突出。

　　3．What can we infer from the text?

　　A．Food sold in city stores is usually unhealthy.

　　B．Most of the children in the program are overweight.

　　C．Compared with healthy food, packaged food is cheaper.

　　D．The problem of overweight is getting worse in the United States.　

　　解析：选D　推理判断题。由最后一段"She notes that the child obesity rate in the United States is twice what it was 30 years ago."可知，美国的儿童肥胖问题更为严重了。

　　B

Whether it's to help their dogs or themselves, about half of all Americans surveyed in a recent poll (民意测验) say they exercise regularly. According to the poll, most people walk for exercise a few times a week. About a third say they walk every day.